an object of 2kg is placed at rest. how much force must be applied on it so that a velocity of 4m/s may be produced in it 4s
Answers
Given:
- Mass of object, m = 2 kg
- Initial velocity of object, u = 0
- Final velocity required, v = 4 m/s
- Time for which force is to be applied, t = 4 s
To Find:
- Force to be applied on the object, F = ?
Formulae required :
- First equation of motion
v = u + a t
- Newton's second law of motion
F = m a
[ Where v is final velocity, u is initial velocity, a is acceleration, t is time taken, F is force applied and m is mass of object ]
Solution :
Using first equation of motion
→ v = u + a t
→ 4 = ( 0 ) + a ( 4 )
→ a = 4 / 4
→ a = 1 m/s²
Using Newton's second law of motion
→ F = m a
→ F = ( 2 ) ( 1 )
→ F = 2 N
Hence,
- A force of 2 Newtons will be required .
Answer:
2N
Explanation:
Given that, an object of 2kg is placed at rest.
We have to find that how much force must be applied on it so that a velocity of 4m/s may be produced in it 4s.
Force is defined as the product of mass and acceleration.
F = ma
Whereas, acceleration is defined as the change in velocity with respect to time taken.
a = (v - u)/t
So,
F = m × (v - u)/t
Simply substitute the values,
→ F = 2 × (4 - 0)/4
→ F = 2 × 4/4
→ F = 2
Hence, the force of 2N is applied on the object.