Question

A body mass 10 kg is moving with a uniform velocity 100 m/s is stopped after 10 sec . find the force and the distance it covered​

Answer 1

Answer:

You are given the following informations which are very important to note down in a systematic way :

Mass (m) = 10 kg

Initial velocity (u) = 100 m/s

Final velocity (v) = 0 m/s

Time taken (t) = 10 s

Acceleration (a) = ? m/s²

Now, a = \frac{v - u}{t}

t

v−u

Or, a \: = - \frac{100}{10}a=−

10

100

m/s²

Or, a = - 10a=−10 m/s²

Here, the negative sign only represents that the acceleration is negative, i.e., retardation occurs.

So, actual retardation = 10 m/s²

Now, F = m × a

Or, F = (10 × 10) N

Or, F = 100 N

Answer 2

Answer:

u = 100 m/s, v = 0 m/s, t = 10 sec

» a = (v - u)/t = -10 m/s²

Therefore, F = ma = - 100 N

Negative sign indicates force is in opposite direction of motion.

» v² = u² + 2as

» 2 (10) s = 100²

» s = 500 m

Hence, the distance covered is 500 m.