Answer:
d. 16 kg-m/s
Explanation:
The new momentum of the swimming fish after eating the stationary fish can be calculated by adding the momentum of the initial swimming fish and the momentum of the stationary fish. Since momentum is a vector quantity, the direction of the momentum is the same as the direction of motion of the fish. If the fish continues to swim with the same velocity after eating the stationary fish, then the new momentum is the sum of the initial momentum of the swimming fish and the momentum of the stationary fish.
Initial momentum of swimming fish = 8 kg-m/s
Momentum of stationary fish = 2 kg * 0 m/s = 0 kg-m/s
New momentum = Initial momentum of swimming fish + Momentum of stationary fish = 8 kg-m/s + 0 kg-m/s = 8 kg-m/s + 2 kg-m/s = 10 kg-m/s.
So, the correct answer is (d) 16 kg-m/s.
Answer:
C
Explanation:
Using law of conservation of momentum of the system
Momentum before = momentum after
8 kg m/s = 8 kg m/s
The second fish has zero momentum, so after eating it the system still has momentum of 8 kg m/s
during which time interval(s) (AB,BC,CD,DE,EF,FG) WAS THE CART AT REST
The time intervals in which the cart is at rest are AB, CD and EF.
What is rest in motion of a cart?
During the motion of a cart, the cart is said to be at rest when the change in the position of the cart with time is zero.
It can also be defined as the points in which the cart is at a constant position during a given time interval or zero speed.
Mathematically, the motion of a cart is determined by applying the following formula as shown below;
v = Δx / Δt
v = ( x₂ - x₁ ) / ( t₂ - t₁ )
where;
x₂ is the final position of the cartx₁ is the initial position of the cartt₂ is the final time of motiont₁ is the initial time of motionThe speed of the cart at point A and B;
v = ( - 5 - ( - 5 ) / ( 5 - 0 ) = 0
The speed of the cart at point C and D;
v = ( - 2 - ( - 2 ) / ( 20 - 11 ) = 0
The speed of the cart at point E and F;
v = ( 8 - 8 ) / ( 40 - 30 ) = 0
Thus, the cart is said to at rest if the speed of the cart is zero.
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A body lifts up a book from the floor to the table. The mass of the box is 300 g and the height of the table is 80 cm. Find the work done by the boy when the acceleration due to gravity is 10 ms-2.
The work done by the boy against the gravitational force is 240000J.
What is the work done?Lifting an object against gravity generates potential energy for the object-Earth system. The change in gravitational potential energy, ΔPEg, is calculated as ΔPEg = mgh, where h is the height increase and g is the acceleration due to gravity.The gravitational pull of the Earth, denoted by g, is the net acceleration imparted to objects by the combined effect of gravitation and centrifugal force.Here given that,
Mass of the box (m) = 300 g
Height of table (h) = 80cm
Acceleration due to gravity (g) = 10 m/s²
Work done against gravitational force will be calculated by formula,
W = mgh
By substituting the values,
= 300 x 10 x 80
= 240000J
Therefore the work done by the boy is 240000J.
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The first practical car to use a gasoline engine was built in London in 1826. The power generated by the engine was just 2984 W. How long would this engine have to run to produce 3.60 × 10^4 J of work?
To find out how long the engine would have to run to produce 3.60 x 10^4 J of work, we first need to determine the power output of the engine. The power generated by the engine is given as 2984 W.
To calculate the time it would take for the engine to produce 3.60 x 10^4 J of work, we can use the formula:
time = work / power
where work is measured in joules and power is measured in watts.
So, we can substitute in the values we know:
time = 3.60 x 10^4 J / 2984 W
If we perform the calculation we will get:
time = 12 seconds
So, the engine would have to run for 12 seconds to produce 3.60 x 10^4 J of work.
I hope this helps :)
12 This question is about a parachutist.
(a) A parachutist leaves a helicopter that is hovering above the ground.
The parachutist is initially at rest and falls vertically downwards.
Calculate the speed of the parachutist after they have fallen through a distance
of 1300m.
Ignore the effect of air resistance.
Answer:
159.6 m/s²
Explanation:
The third equation of motion is
v² = u² + 2gs
where v = final velocity
u = initial velocity or 0 ( body is initially at rest)
g = acceleration due to gravity = 9.8 m/s²
s = 1300 m
v² = 2gs
v² = 2600 x 9.8
v = √(2600 x 9.8
v is approximately 159.6 m/s^2
WHICH IS A LOT.
A particular calculation requires you to multiply kg x m/s² x m.
What are the CORRECT units of the answer? Select ALL that apply.
Elimination Tool
Select all that apply
A J
B N²
C kg/s
D Nm
Answer:Step-1: The first step is to multiply or divide both the linear equations with a non-zero number to get a common coefficient of any one of the variables in both equations. Step-2: Add or subtract both the equations such that the same terms will get eliminated.
A car is traveling at 14 m/s. By what factor does the car's kinetic energy increase if its speed is doubled to 28 m/s?
If speed of the car is doubled to 28 m/s, the kinetic energy of it will be four times.
What is kinetic energy?The energy an object has as a result of motion is known as kinetic energy in physics. It is described as the effort required to move a mass-determined body from rest to the indicated velocity. The body holds onto the kinetic energy it acquired during its acceleration until its speed changes.
Kinetic energy is directly proportional to square of the speed of the object.
Hence, if its speed is doubled to 28 m/s, the kinetic energy of it will be four times.
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Select the correct answer. In a given city, the permissible limit of CO (carbon monoxide) in the air is 100 parts per million (ppm). The city monitors the steady rise of CO from various sources annually. In which year (rounded off to the nearest integer) will the CO level exceed the permissible limit? A. 2017 B. 2018 C. 2019 D. 2022
The year that the CO level exceed the permissible limit is C. 2019
What is the permissible limit?In the US, the permissible exposure limit is the maximum level of exposure to a chemical substance or physical agent, such as high levels of noise. The Occupational Safety and Health Administration establishes permissible exposure limits.
The maximum level of a substance to which a person can be exposed is known as the permissible exposure limit (PEL). When carbon monoxide levels in your bloodstream rise, carbon monoxide poisoning happens. Your body replaces the oxygen in your red blood cells with carbon monoxide when there is too much carbon monoxide in the air. Serious tissue damage or even death may result from this.
When gasoline, wood, propane, charcoal, or other fuels are burned, carbon monoxide, an odorless, tasteless gas, results. Appliances and engines that aren't properly ventilated, especially in a room that's tightly sealed or enclosed, can build up dangerous amounts of carbon monoxide.
In this case, the appropriate year is 2019.
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why the density of an unknown substance in a mixture can be used to identify the substance?
Answer:
Explanation: You may figure out what it is by calculating the density of a substance to be identified and comparing the result to a table of known densities.
Density is also a helpful property since it bridges the gap between the mass and volume of a material. Density=mass/volume. Assume you're tasked with identifying an unknown material. The mass of the material may be calculated using a scale. The volume can be determined by dropping the object into a graduated cylinder containing a known volume of water and measuring the new volume. The density is calculated by dividing the mass by the volume and comparing it to a list of known densities.
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A wave with a frequency of 17 Hz has a wavelength of 5 meters. At what speed will this wave travel?
Answer:
85
Explanation:
soln
given that;
frequency=17Hz
wavelength=5m
speed?
formula for wavelength is;
wavelength= speed/frequency
then ; making v the subject formula
we have that v=wavelength*frequency
v=17*5=>85ms
Analyzing Gravitational Data Quick Check
Which of the following statements about gravitational mass is true? (1 point)
O Gravitational acceleration is irrespective of mass.
O The more mass an object has, the more gravitational acceleration it will experience.
O The less mass an object has, the less gravitational acceleration it will experience.
Gravitational acceleration is always equal to mass.
The true statement about gravitational mass is the more mass an object has, the more gravitational acceleration it will experience.
option B.
What is gravitational acceleration?
The gravitational acceleration of an object is the acceleration an object with mass experiences due to impact of force of gravity on the object.
g = ( GM ) / ( R² )
where;
G is the universal gravitation constantM is the mass of the objectR is the radius of the objectFrom the equation given above, the acceleration of an object increases with increase in the mass of the object and decrease in the radius of the object.
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the most powerful ice breaker in the world was built in the former soviet union.The ship is almost 150 m long, and its nuclear engine generates 56 MegaWatts (56 E^6 W) of power. How much work can this engine do in 1.0 hour? (1 Hour = 3600 seconds)
The most powerful ice breaker can work 2.016 × 10 ¹¹ Joule in 1.0 hour.
What is power?The quantity of energy moved or converted per unit of time is known as power in physics. The watt, or one joule per second, is the unit of power in the International System of Units. Power is also referred to as activity in ancient writings. A scalar quantity is power.
Power of the nuclear engine = 56 × 10⁶ W.
Time it works = 1 hour = 3600 second
Hence, work done by this engine in 1.0 hour = 56 × 10⁶ × 3600 Joule
= 2.016 × 10 ¹¹ Joule.
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If two objects of in equal mass are struck with the same amount of force, what should the result be according to newtons 2nd Law?
Answer:
According to Newton's second law of motion, the net force acting on an object is equal to the mass of the object multiplied by its acceleration, or F = ma.
If two objects of equal mass are struck with the same amount of force, the acceleration of the two objects should be the same. This is because the net force acting on both objects is the same, and their mass is also the same. Therefore, the acceleration of the two objects will be in proportion to the net force acting on them and will be equal.
Atoms are typically spaced about 0.2 nm apart (nucleus to nucleus). At that spacing, how many atoms would be found in a line 4.97 inches long?
Atoms are typically spaced about 0.2 nm apart, which means that there are 5 nm in 1 micrometer (1nm = 0.001 micrometer).
To convert inches to micrometres we can use the conversion factor 1 inch = 25.4 micrometres.
So 4.97 inches is equal to 4.97 x 25.4 = 126.988 micrometres
And if we divide 126.988 micrometres by 5 micrometres we get 25.3976
So, there would be 25 atoms in a line 4.97 inches long.
How can the city with a high relative humidity have so little moisture in the air?
4.og of nacl is heated with mno2 in excess concentrated h2so4 the chlorine gas liberated is then passed through KI solution to liberate iodin. Calculate the mass of mno2
The mass of MnO₂ required by 4 g of NaCl in the chemical reaction is 1.487 g.
What is the balanced chemical reaction of NaCl, MnO₂ and H₂SO₄?
The balanced chemical reaction of NaCl, MnO₂ and H₂SO₄ is given as follows;
4NaCl + MnO₂ + 4H₂SO₄ → MnCl₂ + 4NaHSO₄ + Cl₂ + 2H₂O
From the chemical equation given above, we can calculate the mass of 4NaCl and MnO₂ as follows;
where;
Na is sodium, mass = 23 g/molCl is chlorine, mass = 35.5 g/molMn is manganese, mass = 55 g/molO is oxygen = 16 g/mol4NaCl = 4 ( 23 + 35.5 ) = 234 g
MnO₂ = ( 55 + 32 ) = 87 g
The mass of MnO₂ required by 4 g of NaCl in the chemical reaction is calculated as;
4NaCl + MnO₂ + 4H₂SO₄ → MnCl₂ + 4NaHSO₄ + Cl₂ + 2H₂O
in this equation, 234 g of NaCl ---------> 87 g of MnO₂
4 g of NaCl -------------> ? MnO₂
= ( 4 x 87 ) / ( 234 )
= 1.487 g
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A tumbleweed is bouncing through the desert with a speed of 11 m/s. If the tumbleweed has 199.65 J of kinetic energy, what is the mass of the tumbleweed?
____kg
How do you get part (c)?
Part (a) Which statement best describes the numbers of protons and electrons in the penny when it is charged as indicated?
Electrons were added, and the number of electrons exceeds the
number of protons. ✔ Correct!
Part (b) How many electrons were transferred in order to create the charge on the penny?
Ne = 6.88 * 109
Ne = 6.880×109electrons ✔ Correct!
Part (c) By what percentage do the transferred electrons change the mass of the penny? (Express your result as a positive percentage for an increase, negative for a decrease.)
The percentage at which the transferred electrons change the mass of the penny is 0 %.
What percentage is the mass of the penny changed?
The percentage at which the transferred electrons change the mass of the penny is calculated by applying the following formula as shown below.
Mathematically, the formula for percentage change is given as;
percentage change = ( New mass - old mass ) / ( old mass ) x 100%
The original mass of the copper penny is given as 2.5 g and when converted to kilogram, the mass becomes 0.0025 kg.
The mass of 1 electron = 9.11 x 10⁻³¹ kg
then, the mass of 6.88 x 10⁹ electrons = ?
= ( 6.88 x 10⁹ ) x ( 9.11 x 10⁻³¹ kg )
= 6.27 x 10⁻²¹ kg
new mass of the penny = 0.0025 kg + 6.27 x 10⁻²¹ kg = 0.0025 kg
The percentage change in the mass of the penny is calculated as follows;
percentage change = ( New mass - old mass ) / ( old mass ) x 100%
percentage change = ( 0.0025 kg - 0.0025 kg ) / ( 0.0025 kg ) x 100%
percentage change = 0 %
Thus, the transferred electron has no effect on the mass of the penny because the mass an electron is almost insignificant.
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Describe how to demonstrate the thermal energy is dissipated from a cup of hot tea
Answer:
Explanation:
1. Place a cup of hot tea on a flat surface.
2. Place a thermometer in the tea and record the temperature.
3. Place a fan in front of the cup of tea and turn it on.
4. Place the thermometer in the tea again and record the temperature.
5. Compare the two temperatures and observe the difference.
6. The difference in temperature is an indication of the thermal energy that has been dissipated from the cup of hot tea.
Two masses m1 = 15 kg and m2 = 25 kg are joined by connecting a rod of length 0.8 m. Determine the distance of the CM of the system from the m1 if: (a) the connecting rod is massless, and (b) the connecting rod is a uniform rod of mass 15 kg.
Answer:
a) When the connecting rod is massless, the center of mass (CM) of the system is located at the point where the two masses are joined. Therefore, the distance of the CM from m1 is 0.8 m.
b) When the connecting rod is a uniform rod of mass 15 kg, the position of the CM of the system can be found using the parallel axis theorem. The formula for the parallel axis theorem is:
CM = (m1d1 + m2d2 + m3*d3)/(m1 + m2 + m3)
where m1, m2, and m3 are the masses of the two masses and connecting rod, respectively, and d1, d2, and d3 are the distances of their respective CM from the reference point.
In this case, m1 = 15 kg, m2 = 25 kg, m3 = 15 kg, d1 = 0, d2 = 0.8 m, and d3 = 0.4 m (half of the length of the connecting rod).
Substituting these values into the formula, we get:
CM = (150 + 250.8 + 15*0.4)/(15 + 25 + 15) = 0.48 m
So the distance of the CM of the system from m1 is 0.48 m.
An increase in what property of an object causes its interia to increase? Volume velocity acceleration mass
Mass.
Mass, in physics, quantitative measure of inertia, a fundamental property of all matter. It is, in effect, the resistance that a body of matter offers to a change in its speed or position upon the application of a force. The greater the mass of a body, the smaller the change produced by an applied force.
A tuning fork is vibrating the air around it. What best describes the waves produced by the tuning fork?
The waves produced by a vibrating tuning fork are longitudinal waves, also known as compression waves.
What are Longitudinal Waves?Longitudinal waves are waves that oscillate along the direction of propagation, meaning they create alternating regions of compression and rarefaction in the medium through which they travel.
In the case of a vibrating tuning fork, the tines of the fork move back and forth, causing the surrounding air to alternately compress and expand. These pressure changes propagate through the air as longitudinal waves.
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define microgravity and a condition under which it can be produced.
Answer:
see below
Explanation:
Microgravity is a condition in which the gravitational force experienced by an object is very weak. It is characterized by a very small gravitational acceleration, typically less than one thousandth of that experienced on Earth's surface. The gravitational force experienced in microgravity is so small that it is often neglected in many physical phenomena.
A condition under which microgravity can be produced is by placing an object in a state of freefall. Freefall is the state in which an object is falling under the influence of gravity, but it is not in contact with a solid surface. When an object is in freefall, it experiences a condition of weightlessness, which is similar to microgravity.
One of the ways to produce microgravity is by being in orbit around the Earth, at an altitude of around 200 miles or more, the gravitational pull is weak enough to be considered as microgravity. This can be achieved by using spacecrafts or high-altitude balloons, where the object is in a state of free fall around the Earth, and it experiences microgravity.
Another way to achieve microgravity is by using aircrafts, such as the "vomit comet" that flies in parabolic trajectory, allowing the passengers to experience weightlessness for a few minutes during the flight.
A galvanometer of resistance 50 ohms which gives a full scale deflection for 1M.A is to be adapted to measure current of up to 5A.-calculate tht resistance of the resistor required.- if this resistor is made of a material of cross-sectional area 4*10^-4cm2 and resistivity 2*10^-6cm2 calculate it's length
Answer:
Explanation:
R = (50 ohms x 5A) / 1mA = 250 ohms
The resistance of the resistor is 250 ohms.
The resistivity (ρ) = 2 x 10^-6 cm^2
The cross-sectional area (A) = 4 x 10^-4 cm^2
Therefore, the length (l) = (ρ x R) / A
l = (2 x 10^-6 cm^2 x 250 ohms) / (4 x 10^-4 cm^2)
l = 1.25 cm
What force causes fluid pressure to vary with depth? Explain why this happens.
The force that causes fluid pressure to vary with depth is the weight of the fluid. As the fluid is a form of matter, it has weight and it exerts a force due to its weight. This force is known as hydrostatic force or pressure.
When the fluid is at rest, the weight of the fluid acts vertically downwards and it exerts pressure on the bottom of the container or on any object submerged in it. The deeper the object is, the more fluid is above it, and the greater the weight of the fluid is, so the greater the pressure is.
This happens because of the concept of Archimedes' principle which states that the buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid that the object displaces. So the deeper an object is submerged in a fluid, the more fluid it displaces, and the greater the buoyant force is. This buoyant force also known as the upthrust is what opposes the weight of the fluid and causes the pressure to vary with depth.
A new planet is observed to orbit a 6.1x1030kg star. If astronomers calculate the planet to have a mass of 4.8x107 kg and an average distance of 1.3x1012meters from it's star, what is the gravitational force between the star and the new planet? (G=6.673x10−11 )
The force that is acting on the bodies is obtained as 1.15 * 10^- 48 N.
What is the force?Let us have it at the back of our minds that the force that is acting between the star and the planet has to be an attractive force since it is the force of gravity. Now we know that;
F = Gm1m2/r^2
F = force of gravity
m1 and m2 are the masses of the objects
r = The distance between the objects
Then;
F = 6.673x10^−11 * 6.1x10^30 * 4.8x10^7/(1.3x10^12)^2
F = 1.95 * 10^-24/1.69 * 10^24
F = 1.15 * 10^- 48 N
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Q2 The equation of the periodic time of a pendulum
bob is:
T= 2√L/g
2514
Where T is the periodic time. I is the length of the
string.
A Prove that the equation is homogeneous with respect to e base Units
B. Find the base unit of force.
The dimensional relation of the time period bob with its length is shown below.
what is meant by "dimensional analysis"?a method of analysis that represents physical quantities in terms of their fundamental dimensions in the absence of enough data to create precise equations.
What is the purpose of dimensional analysis?Dimensional analysis is a method used in engineering and the physical sciences to reduce physical quantities like acceleration, viscosity, and energy to their three basic dimensions of length, mass, and time (T).
[T]=[M^0 L^0 T^1]
[L]=[M^0 L^1 T^0]
[g]=[M^0 L^1 T^-2]
SQUARE ROOT OF (L/g)=[m0l1t0]/[m0l1t-2]
=[m0l0t1]
= R.H.S.
Hence it's dimensionally correct.
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1. You start your bicycle ride at the top of a hill. You coast down the hill at a constant acceleration of 2.00 m/s2. When you get to the bottom of the hill, you are moving at 18.0 m/s, and you pedal to maintain that speed. If you continue at this speed for 1.00 min, how far will you have gone from the time you left the hilltop?
Answer:
Explanation:
In order to determine how far you will have gone after 1.00 min, we need to calculate the distance traveled while coasting down the hill and the distance traveled while pedaling.
To calculate the distance traveled while coasting down the hill, we can use the equation:
distance = initial velocity * time + (1/2) * acceleration * time^2
Since you start at the top of the hill with an initial velocity of 0 m/s, and we know that the acceleration is 2.00 m/s^2, and time is unknown. we can solve for time using the final velocity equation:
velocity = acceleration * time + initial velocity
18 = 2*t + 0
t = 9 sec
Now we have time and acceleration, we can calculate distance.
distance = 0 * 9 + (1/2) * 2 * 9^2
distance = 81 m
Now we know how far you have traveled while coasting down the hill, we can calculate the distance traveled while pedaling.
We know that you are pedaling to maintain a constant speed of 18.0 m/s for 1.00 min, so we can use the formula:
distance = speed * time
distance = 18 * 1*60 = 1080 m
Therefore, in total, you have traveled 1080 + 81 = 1161 m from the time you left the hilltop.
An iron meteorite melts when it enters the Earth's atmosphere.
If its initial temperature was -105°C outside of Earth's atmosphere, calculate the minimum velocity the meteorite must have had before it entered Earth's atmosphere.
The minimum velocity for the meteorite before entrance into earth's atmosphere is 36.8 m/s.
How to find minimum velocity?To calculate the minimum velocity the meteorite must have had before it entered Earth's atmosphere, the equation for heat transfer is:
Q = mcΔT
Where Q = the heat transferred,
m = the mass of the meteorite,
c = the specific heat capacity of iron, and
ΔT = the change in temperature.
The specific heat capacity of iron is approximately = 0.45 J/g°C.
Temperature of the meteorite changes from -105°C to the melting point of iron, which is approximately = 1535°C.
So: Q = mc(1535 - (-105))
Mass of the meteorite unknown, but we know it is made of iron, so assume a value for the mass, such as 100 g.
Q = 100 x 0.45(1535 - (-105))
Solving for Q:
Q = 67875 J
To calculate the kinetic energy of the meteorite, which is given by the equation: Ek = 1/2mv²
where Ek is kinetic energy,
m = the mass of the meteorite and
v = the velocity of the meteorite.
Therefore, the velocity of the meteorite is given by the following equation: v = √(2Ek/m)
Substituting the values of Ek and m, we get
v = √(2 x 67875/100)
Solving for v:
v = √1357.5
The minimum velocity the meteorite must have had before it entered Earth's atmosphere is approximately 36.8 m/s.
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You weigh 650 N.
What would you weigh if the Earth were
five times as massive as it is and its radius
were five times its present value?
Answer in units of N.
Answer:
129.95 N
Explanation:
First, you want to find the acceleration due to gravity on this hypothetical planet.
Using the equation [tex]g = G (M/R^2)[/tex] , where G is a constant ([tex]6.67 * 10^{-11}[/tex]), M is mass of the planet, and R is radius of the planet, we can plug in the numbers of earth and then multiply them by whatever the question requires, in this case, 5x.
[tex]g = (6.67 * 10^{-11})(5*(5.97 * 10^{24})) /(5* (6.378 *10^{6}))^{2}[/tex]
g = 1.96 m/s. The acceleration due to gravity on this planet is 1.96 m/s.
Now to find your weight.
First, you want to find your mass.
On earth, your weight is equal to your natural force (Fn)
mg = Fn
m(9.8) = 650 ==> mass = 66.33 kg
Now, to find your weight on this hypothetical planet, multiply your mass by the acceleration due to gravity (g)
M x g
66.33 x 1.96 = 129.95 N
You would weigh 129.95 N
the velocity of a particle is given by v(t) = 20t²-100t+50t. a, when will the acceleration of a particle is zero. b, what is the velocity of the particle when it's acceleration is zero.
Answer:V(t)=20t^2-100t+50t
as we know accl means derivatives of velocity.
a/q,
dv/dt =0
dv/dt=20t^2-100t+50t=0
dv/dt=4t-100+50=0
=>40t-50=0
=>40t=50
=>t=1.25
therfore Vs= 20t^2-100t+50t
Vs=20(1.25625)-125+62.5
Vs=31.25-125+62.5
Vs=-31.25