The work done in pulling the sled is 445,930.2 Joules.
The acceleration in the x direction, assuming that friction is negligible, is 20.85 m/s².
Time taken to pull the sled 185 m is 4.21s.
What is work done?Work done is equal to product of force applied and distance moved.
Given is a 545 N sled is pulled a distance of 385 m. The task is done by pulling on a rope with a force of 1225 N at an angle of 19° with the horizontal.
Work = Force x Distance x cos(angle)
W= 1225 x 385 x cos 19°
W = 445,930.2 Joules
Thus, the work done in pulling the sled is 445,930.2 Joules
From the Newton's second law of motion, we have'
F = ma
acceleration, a = 1225cos19° / ( 545 /9.81)
a = 20.85 m/s²
Thus, the acceleration in the x direction is 20.85 m/s²
Using the second equation of motion, we get
s = ut+ 1/2 at²
Substitute the values, we have
185 m = 0 +1/2 x 20.85 x t²
t = 4.21 s
Thus, the time taken to pull the sled 185 is 4.21s.
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Which statement about the accuracy and precision of measuring tools is
true?
OA. A tool can be both accurate and precise.
о B. Tools that are precise must also be accurate.
о C. Tools cannot be both accurate and precise.
O D. A tool that is accurate lacks precision.
The true statement about the accuracy and precision of measuring tools is Tools cannot be both accurate and precise. The correct option is C.
What is accuracy?When in an experiment, a value is measured 5 times, then if the values measured are same for most of the time or like three times out of five, it said to be accurate. The phenomenon is accuracy.
Precision is about comparing the values to each other then find them near to each other.
Accuracy compares the experimental value to the theoretical value.
So, when all the values are close to each other but not nearest to the theoretical value, then it is said to be precise but not accurate.
Thus, the correct option is C.
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what happens when a force is applied to an object while the object moves in a direction opposite to the force?
a. negative work is done
b. work is done only if the force causes a decrease in speed
c. positive work is done
d. work is done only if the force causes an increase in speed.
Answer:
the anser is b
Explanation:
If the force applied on the object is in the direction of its motion, the speed of the object increases. If the force is applied in the direction opposite to the direction of motion, then it results in a decrease in the speed of the object.
What will be the temperature reading in Fahrenheit scale whe eading is 310 k?
The temperature reading in Fahrenheit scale when reading 310 K is 98.6F
What is temperature?
Temperature is the degree of hotness or coldness of the object.
Given is a temperature in Kelvin scale = 310 K
Temperature on centigrade scale = 310 -273 = 37°C
Temperature conversion from Centigrade to Fahrenheit is
C/5 = F -32/9
Plug the value, we get
37/5 = F-32/9
66.6 = F -32
F = 32+66.6 =
F = 98.6
Thus, the temperature of 310 K in Fahrenheit is 98.6F.
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A circular wheel of mass 50 kg and radius 200 mm is rotating at 300 r.p.m. Find its kinetic energy.
Across:
5. The term used for describing the
bending of an arm or a leg
6.
9.
Down:
1. This is one popular brand of exercise
machine
2.
They are made of two types of fibers
You can achieve your target pulse rate
by varying the number of these
flexes the arms at
10. The arm
the elbows
11. These muscle fibers do not require as
much oxygen
13. He wrote a book on aerobics
14. This type of training works primarily
with the white muscle fibers
15.
extends the legs at the
The leg
knees
16. Aerobic exercises help the body's
ability to use this element
18.
The term used to describe the straight-
ening of your arm or leg
3.
4.
5.
6.
7.
8.
This was the most popular form of aerobic
exercise in the early years of aerobics
This organ is one part of the cardiovascu-
lar system
This exercise conditions the cardiovascu-
lar system
Aerobic exercise became part of this
movement in the 1970s
12.
17.
This accompanies aerobic dance
A specific exercise produces this type of
result
This type of training involves moving
from one exercise machine to another with
little rest
If you just train for strength, you will not
improve this
These muscle fibers contract more slowly
Answer:hight
Explanation:
A 50 N force is applied to the free end of a spiral spring of force constant, 100 Nm
Calculate the work done by the force to stretch the spring.
The work done by the force to stretch the spring is determined as 12.5 J.
Work done by the forceThe work done by the force to stretch the spring is calculated as follows;
W = ¹/₂Fx
F = kx
W = ¹/₂F(F/k)
W = ¹/₂F²/k
W = ¹/₂ x (50²)/100
W = 12.5 J
Thus, the work done by the force to stretch the spring is determined as 12.5 J.
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loade Brack Figure below show a circuit diagram of a device for controlling the temperature in a room. Explain how the Iron Heating element S loade Brack Figure below show a circuit diagram of a device for controlling the temperature in a room . Explain how the Iron Heating element S
Answer:
suna bro i am nepali and nepali are pro
Need help with this question!!
A beta particle or an electron is released during beta decay. The charges can be positive or negative. Co changes to Ni, Fe to Mn, Pb to Tl, and Pu to Am.
What is beta decay?Beta-decay is the radioactive decay that involves the release of the beta particle or the positron or the electron. The larger nucleus splits during nuclear fission and releases smaller nuclei.
The nuclear reactions are shown as:
⁶⁰Co₂₇ → ⁶⁰Ni₂₈ + ⁰e₋₁⁵⁶Fe₂₆ → ⁵⁶Mn₂₅ + ⁰e₋₁²¹⁰Pb₈₂ → ²¹⁰Tl₈₁ + ⁰e₋₁²⁴¹Pu₉₄ → ²⁴¹Am₉₅ + ⁰e₋₁Learn more about beta decay here:
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i need help with lab
(a) The equilibrant C for force of vector A and B is 3.43 N.
(b) The equilibrant C for fx of vector A and B is 2.1 N.
(c) The equilibrant C, for fy of vector A and B is 2.12 N.
What is equilibrant force?An equilibrant force is a single force that will bring other bodies into equilibrium.
From configuration 1:Vector A: mass = 0.2 kg, θ = 20⁰
Vector B: mass = 0.15 kg, θ = 80⁰
Fx = mg cosθ
Fy = mg sinθ
where;
m is mass g is acceleration due to gravityVector AForce of A due to its weight
F(A) = mg
F(A) = 0.2 x 9.8 = 1.96 N
Fx = (0.2 x 9.8) cos(20) = 1.84 N
Fy = (0.2 x 9.8) sin(20) = 0.67 N
Resultant forceR = √(0.67² + 1.84²)
R = 1.96 N
Vector BForce of B due to its weight
F(B) = mg
F(B) = 0.15 x 9.8
F(B) = 1.47 N
Fx = (0.15 x 9.8) cos(80) = 0.26 N
Fy = (0.15 x 9.8) sin(80) = 1.45 N
Resultant forceR = √(0.26² + 1.45²)
R= 1.47 N
Equilibrant C of vector A and BEquilibrant force:
Force, C = 1.96 N + 1.47 N
Force, C = 3.43 N
Equilibrant FX:
Fx, C = Fx(A) + Fx(B)
Fx, C = 1.84 N + 0.26 N = 2.1 N
Equilibrant FY:
Fy, C = Fy(A) + Fy(B)
Fy, C =0.67 N + 1.45 N = 2.12 N
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Two students have fitted their scooters with the same engine. Student A and his
scooter have a combined mass of 127.5 kg and a maximum acceleration of
2.40 m/s². Student B has a maximum acceleration of 1.70 m/s on her scooter.
Show that the combined mass of student B and her scooter is 120 kg
You may assume that the frictional forces acting on each scooter are negligible.
The force exerted by student A with his scooter is 306 N and that of student B is 204 N.
Force applied by each studentThe force exerted by each student is calculated from Newton's second law of motion.
F = ma
where;
m is mass a is accelerationF(A) = 127.5 x 2.4
F(A) = 306 N
F(B) = 120 x 1.7
F(B) = 204 N
Thus, the force exerted by student A with his scooter is 306 N and that of student B is 204 N.
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What must the charge (sign and magnitude) of a particle of mass 1.45 g be for it to remain stationary when placed in a downward-directed electric field of magnitude 600 N/C ? Use 9.80 m/s2 for the magnitude of the free-fall acceleration.
[tex]q = -21 * 10^{-6} C[/tex]
What is Free-fall acceleration?The acceleration is constant and equal to the gravitational acceleration g which is 9.8 m/s at sea level on the Earth.
As we know that charge and its sign that remains in equilibrium is under gravity must be such that it will balance the gravitational force by electric force,
mg =qE
[tex]1.45 * 10^{-3}(9.80)=q(600)\\\\q = 21 *10^{6} C\\\\[/tex]
and its sign must be negative so that it will have upward electric force
so it is
[tex]q = -21 * 10^{-6} C[/tex]
The charge of a particle of mass is [tex]-21 * 10^{-6} C[/tex]
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As a warehouse worker pushes a crate across a concrete floor, the force he
applies is not perfectly horizontal, as shown in the image below. If the
coefficient of kinetic friction between the crate and concrete floor is 0.5, what
is the net force on the crate?
A. 136 N
B. 99 N
C. 73 N
D. 112 N
The net force on the crate will be 99 N.Option B is correct.
What is the friction force?It is a type of opposition force acting on the surface of the body that tries to oppose the motion of the body. its unit is Newton (N). it is defined as the product of the coefficient of friction and normal reaction.
On resolving the given force and acceleration.Mathematically in the different components and balancing the equation gets.Components in the x-direction.
When all the forces get resolved the y-direction of forces are;
300 sin 10° +N = 445
N = 445-295.4
N = 392.9 N
The normal force is 392.9 N.
The net force on the crate is found by resolving the force in the x-direction;
F = 300 cos 10° - μN
F= 295.44-196.45
F= 98.99
F=99
Hence, the net force on the crate will be 99 N.Option B is correct.
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question is below............
The total distance traveled by the gardener is 8 meters. the magnitude of total displacement is approximately 7 meters.
Total distance covered by gardener = 2 + 1 +2 + 3= 8 meters
For the magnitude of displacement, we will take the shortest path for the gardener movement.
for displacement-
[tex]=\sqrt{( 0-4^{2}) +( 6-0^{2} )}\\=\sqrt{52} \\=7[/tex](approximately)
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If have a custom made telescope with these specifications then what's the focal length of my telescope? (refractor telescope only please)
_Specifications:_
*Objective diameter*: 90mm
*Distance between lenses*: 230mm
*Eyepiece focal length*: 4mm
*Eyepiece size*: 31.7mm
Please respond fast. Also please give a simplified answer for a brainliest answer tag. Thanks!
Answer:
i don't know sorry
i know a good website that may help you
it's called https://skyandtelescope.org/observing/telescope-calculator/
Explanation:
If two balls have the same mass, but ball P is twice as large as ball Q, which one will have the greater density?
a. Ball P
b. ball Q
c. Their densities are equal
a. Ball P
What is density.Density is define as mass per unit volume or the quantity per unit volume, unit area, or unit length.
If [tex]m_{1}[/tex] is mass , [tex]V_{1}[/tex] is volume and [tex]D_{1}[/tex] is density of ball P
[tex]m_{2}[/tex] is mass , [tex]V_{2}[/tex] is volume and [tex]D_{2}[/tex] is density of ball Q
It is given that ,
[tex]V_{1}[/tex] = [tex]V_{2}[/tex];
But [tex]m_{1}[/tex]= [tex]2m_{2}[/tex]
Based on above equation we have:
[tex]\frac{D_{1} }{D_{2} } = (\frac{m_{1} }{V_{1} } )* (\frac{m_{2} }{V_{2} } )\\ \\= (\frac{2m_{2} }{V_{2} })*(\frac{V_{2} }{m_{2} }) \\\\= 2[/tex]
Thus, density of ball P is twice that of Q.
Therefore ,
Ball P will have a greater density than Q
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Which is the correct unit for electrical power?
Answer:
As electrical power is measured in Watts (W), therefore it must be also be measured in Joules per Second. So we can correctly say that: 1 watt = 1 joule per second (J/s).
Explanation:
. Bobby and Alice are pushing a stalled car in the same direction. The mass of the car is 2,000 kg. Bobby applies 400 N to the car while Alice applies 300 N. A force created by friction is 500 N in the opposite direction. What is the acceleration of the car?
Bobby and Alice are pushing a stalled car in the same direction. The mass of the car is 2,000 kg. Bobby applies 400 N to the car while Alice applies 300 N. A force created by friction is 500 N in the opposite direction is the acceleration of the car is 0.1 m/sec.
What is acceleration?An acceleration, fee at which pace adjustments with time, in phrases of each velocity and direction. A factor or an item shifting in a direct line is expanded if it hurries up or slows down.
Is summarized via way of means of the equation: Force (N) = mass (kg) × acceleration (m/s²).The mass = 2000 kg and force= 1200 N. So mass / force = 2000/1200 = 0.1 m/sec.
Thus, the acceleration of the car s 0.1 m/sec.
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A surfer on top of a wave takes 10 seconds to travel a distance of 40 meters. What is the speed of the wave the surfer is riding on?
Select one:
a. 0.25 m/s
b. 4 m/s
c. 40 m/s
d. 400 m/s
Answer:
B. 4 m/sExplanation:
The formula for Speed is distance per time.
Therefore Speed = Distance / TimeData
D = 40 m
T = 10 sec
S = ?
Speed = 40m /10sec
To find the speed , divide the distance by the time.
Note : the unit for Speed is meter /second
Speed = 4 m/sTherefore the speed of the wave, the surfer is riding on is 4 m/s.
An elevator is moving in an upwards direction. The free body diagram for the forces acting on the elevator during this time is: The motion of the elevator can best be described as:
The motion of the elevator can best be described as motion against gravity with negative acceleration.
What is motion?Motion refers to a change in position of an object when it moves from one point another along a reference frame.
An object moving in a downward direction is moving in a positive direction and its velocity increases relative to the earth since gravity acts downwards.
An object moving in a upward direction is moving in a negative direction and its velocity decreases relative to the earth since gravity acts downwards.
Therefore, the motion of the elevator can best be described as motion against gravity with negative acceleration.
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3. Planet 1 has mass M₁ and radius R₁. Planet 2 has mass M₂ and radius
R₂. The two planets are a distance of L apart, measured from surface to
surface. An object is launched with some initial speed from the surface of
Planet 1 directly towards Planet 2. For this problem, assume that Planets
1 and 2 are stationary. (20 points)
(a) At what initial speed must the object be launched so that it reaches
the surface of Planet 2 with zero speed?
(b) Derive an inequality between M₁ and M₂ that represents when (a)
can occur.
(c) Show that, using your result in (b), if R₁ = R₂, then M₁ must be
greater than M₂.
(a) The initial speed must the object be launched so that it reaches
the surface of Planet 2 with zero speed is √[2G{ M₁/ R₁ + M₂/(R₂ + L) - M₁/ (R₁ +L) - M₂/ R₂}]
(b) An inequality between M₁ and M₂ that represents when (a)
can occur is { M₁/ R₁ + M₂/(R₂ + L) - M₁/ (R₁ +L) - M₂/ R₂} ≥ 0
(c) if R₁ = R₂, then M₁ must be greater than M₂ is proved.
What is gravity?The force of attraction felt by a person which is directed at the center of a planet or Earth is called as the gravity.
The force of attraction is directly proportional to the product of masses of the object and inversely proportional to the square of distance between them.
F = GMm/R²
Given, Planet 1 has mass M₁ and radius R₁. Planet 2 has mass M₂ and radius R₂. The two planets are a distance of L apart, measured from surface to surface. An object is launched with some initial speed from the surface of Planet 1 directly towards Planet 2. For this problem, assume that Planets1 and 2 are stationary.
If v is the launch velocity, then initial total energy will be
T.E = 1/2 mv² + ( -GM₁m/ R₁ - G M₂m/(R₂ + L)
The final total energy will be
T.E =0 + ( -GM₁m/ (R₁ +L) - G M₂m/ R₂)
From energy conservation principle, we get
1/2 mv² + ( -GM₁m/ R₁ - G M₂m/(R₂ + L) = ( -GM₁m/ (R₁ +L) - G M₂m/ R₂)
v = √[2G{ M₁/ R₁ + M₂/(R₂ + L) - M₁/ (R₁ +L) - M₂/ R₂}]
(b) an inequality between M₁ and M₂ so that object reaches the surface of Planet 2 with zero speed is
[2G{ M₁/ R₁ + M₂/(R₂ + L) - M₁/ (R₁ +L) - M₂/ R₂}] =0
{ M₁/ R₁ + M₂/(R₂ + L) - M₁/ (R₁ +L) - M₂/ R₂} ≥ 0
Thus, this is an inequality between M₁ and M₂.
(c) If R₁ = R₂, then
{ M₁/ R₁ + M₂/(R₂ + L) - M₁/ (R₁ +L) - M₂/ R₂} ≥ 0
M₁(R+L) + M₂R - M₁R -M₂(R+L) / R (R+L) ≥ 0
M₁(R+L) + M₂R - M₁R -M₂(R+L) ≥ 0
M₁L - M₂L ≥ 0
M₁ ≥ M₂
M₁ must be greater than M₂.
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the projectile thrown with the same initial velocity , one at an angle theta and the other at an angle 90-theta can both projectiles strike at the same distance from the projection point? can both projectiles be in air for the same time interval?
Answer:
If theta is equal to 90, then both projectiles strike at the same distance from the projection point and projectiles are in air for the same time interval.
Explanation:
HELP!! ASAP!!
The purple and blue characters represent atoms, and the red dots represent electrons. Explain the meaning of the cartoon image below as it relates to electronegativity. Which atom is more electronegative? Why? In addition, also explain where the most electronegative atoms are located on the periodic table.
The most electronegative atoms are located in the seventeenth group of the periodic table.
What is electronegativity?
The term electronegativity refers to the ability of an atom to attract the electrons of a bond towards itself. The more electronegative atom will have the electron pairs closer to itself.
Hence, in this case, the blue atom is more electronegative. The most electronegative atoms are located in the seventeenth group of the periodic table.
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imagine your lifting a toy car above your head and then holding it stationary above your head. While it is stationary what forces do you think act on the toy car
Gravity and normal forces act on the toy car.
What is force?A push or pull that an object experiences as a result of interacting with another item are known as a force. Every time two items interact, a force is exerted on each of the objects. The force is no longer felt by the two objects when the interaction ends. Only when there is interaction do forces actually exist.Both contact forces and forces coming from the action at a distance can be used to categorize all forces (interactions) between objects.Frictional forces, tensional forces, normal forces, air resistance forces, and applied forces are a few examples of contact forces.Gravitational forces are examples of action-at-a-distance forces.The standard metric unit known as the Newton is used to quantify force. "N" stands for Newton in abbreviation.To learn more about force refer to:
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what's the difference between coplanar forces and resultant forces?
Answer:
coplanar When all forces are acting in the same
resultunt the single force and associated torque obtained by combining a system of forces and torques acting on a rigid body via vector addition
What is the force of gravity in water
Example 3 :
A liquid with relative density 0.9 and dynamic viscosity of 0.06 Pas
flows in a cast iron pipe of length 100 m and diameter 120 mm.
Determine the friction factor using formula method, and then
calculate the head loss using the answer obtained then using
friction factor formula when the velocity is:
a) 1 ms-1
b) 3 ms-1
The friction factor and head loss when velocity is 1m/s is 0.289 and 1.80 × 10^8 respectively. Also, the friction factor and head loss when velocity is 3m/s is 0.096 and 5.3 × 10^8 respectively.
How to determine the friction factorUsing the formula
μ = viscosity = 0. 06 Pas
d = diameter = 120mm = 0. 12m
V = velocity = 1m/s and 3m/s
ρ = density = 0.9
a. Velocity = 1m/s
friction factor = 0. 52 × [tex]\frac{0. 06}{0. 12* 1* 0. 9}[/tex]
friction factor = 0. 52 × [tex]\frac{0. 06}{0. 108}[/tex]
friction factor = 0. 52 × 0. 55
friction factor [tex]= 0. 289[/tex]
b. When V = 3mls
Friction factor = 0. 52 × [tex]\frac{0. 06}{0. 12 * 3* 0. 9}[/tex]
Friction factor = 0. 52 × [tex]\frac{0. 06}{0. 324}[/tex]
Friction factor = 0. 52 × 0. 185
Friction factor [tex]= 0.096[/tex]
Loss When V = 1m/s
Head loss/ length = friction factor × 1/ 2g × velocity^2/ diameter
Head loss = 0. 289 × [tex]\frac{1}{2*6. 6743 * 10^-11}[/tex] × [tex]\frac{1^2}{0. 120}[/tex] × [tex]\frac{1}{100}[/tex]
Head loss = 1. 80 × 10^8
Head loss When V = 3m/s
Head loss = [tex]0. 096[/tex] × [tex]\frac{1}{1. 334 *10^-10}[/tex] × [tex]\frac{3^2}{0. 120}[/tex] × [tex]\frac{1}{100}[/tex]
Head loss = 5. 3× 10^8
Thus, the friction factor and head loss when velocity is 1m/s is 0.289 and 1.80 ×10^8 respectively also, the friction factor and head loss when velocity is 3m/s is 0.096 and 5.3 ×10^8 respectively.
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Which force is reasonable for making fusion possible in the sun?
The force is reasonable for making fusion possible in the Sun is heat energy.
What is nuclear fission and fusion?When the slow moving neutrons are bombarded with the heavy radioactive nuclei, the product is the more number of neutrons are produced with the large amount of energy. This multiplying process is called nuclear fusion.
The amount of energy produced in such a reaction can be calculated using the equivalence of mass and energy relationship.
E = mc²
The same happens in nuclear fusion where large amount of energy is needed to make more heavy nuclei.
Thus, fusion requires heat energy to continue the reaction.
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3
012 10.0 points
A car with mass 1060 kg crashes into a wall.
The car's velocity immediately before the col-
lision was 14.6 m/s and the bumper is com-
pressed like a spring with spring constant
1.14 × 107 N/m.
What is the maximum deformation of the
bumper for this collision?
Answer in units of m.
013 10
Hi there!
The maximum deformation of the bumper will occur when the car is temporarily at rest after the collision. We can use the work-energy theorem to solve.
Initially, we only have kinetic energy:
[tex]KE = \frac{1}{2}mv^2[/tex]
KE = Kinetic Energy (J)
m = mass (1060 kg)
v = velocity (14.6 m/s)
Once the car is at rest and the bumper is deformed to the maximum, we only have spring-potential energy:
[tex]U_s = \frac{1}{2}kx^2[/tex]
k = Spring Constant (1.14 × 10⁷ N/m)
x = compressed distance of bumper (? m)
Since energy is conserved:
[tex]E_I = E_f\\\\KE = U_s\\\\\frac{1}{2}mv^2 = \frac{1}{2}kx^2[/tex]
We can simplify and solve for 'x'.
[tex]mv^2 = kx^2\\\\x = \sqrt{\frac{mv^2}{k}}[/tex]
Plug in the givens and solve.
[tex]x = \sqrt{\frac{(1060)(14.6^2)}{(1.14*10^7)}} = \boxed{0.0198 m}[/tex]
Question 1 of 25
In the covalent compound CO₂, the Greek prefix used to represent the anion is
Answer:
di
Explanation:
The prefix is di. CO2 is carbon dioxide. di means 2.
A force of 5.25 newtons acts on an object of a mass 25.5 kilograms. How far is the object from the center of Earth? (The value of G is 6.673 × 10-11 newton meter2/kilogram2. The mass of Earth is 5.98 × 1024 kilograms.)
Answer:
The force between two objects is calculated through the equation,
F = Gm₁m₂/d²
where m₁ and m₂ are the masses of the objects. In this case, an unknown mass and Earth. d is the distance between them and G is the universal gravitation constant.
In the second case, if the force is to become 2.5 times the original and all the variables are constant except d then,
2.5F = Gm₁m₂ / (D²)
D = 0.623d
Subsituting the known value of d,
D = 0.623(6.9 x 10^8) = 4.298 x 10^8 m
