A body starts from rest and rolls down a hill with a constant
acceleration. If it travels 400m in 20s, Calculate the force acting on the
body if its mass is 10kg.
Answers
Given:-
- Initial Velocity of body = 0m/s
- Distance travelled = 400m
- Time Taken = 20s
- Mass of Body = 10kg
To Find
- The Force acting on the Body;
Formulae Used:-
- S = ut + ½ × a × t²
- F = ma
Where,
S = Distance
u = Initial Velocity
a = Acceleration
t = Time
F = force
m = Mass
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Now,
S = ut + ½ × a × t²
S = 0 × 20 + ½ × a × 20²
400 = 0 + ½ × a × 400
400 = 200a
a = 400/200
a = 2m/s²
Hence, The Acceleration of the car is 2m/s²
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Therefore,
F = ma
F = 10 × 2
F = 20N.
Hence, The Force acting on body is 20N.
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Explanation:
Given that a body starts from rest and rolls down a hill with a constant acceleration. If it travels 400m in 20s.
We have to find the force acting on the body if its mass is 10kg.
From above data we have, u is 0 m/s, s is 400 m, t is 20s and mass is 10 kg.
Using the second equation of motion,
s = ut + 1/2 at²
Substitute the values,
→ 400 = 0(20) + 1/2 × a × (20)²
→ 400 = 0 + 400a/2
→ 400 = 200a
→ 2 = a
Therefore, the acceleration of the body is 2 m/s².
Now,
Force is defined as the product of mass and acceleration.
F = ma
F = 10 × 2
F = 20
Hence, the acting on the body is 20N.