Question

A 200 N force acts on a block of mass 50 kg kept on horizontal surface which provides 50 N of friction. The speed of block after 5 seconds is (Assume block is initially at rest)

Answer 1

Answer:

The speed of the block whose mass is 50kgs on which 200N of force acts horizontally and the horizontal surface on which the block is placed exerts 50N of friction is 15m/s

Explanation:

Let us assume the value of g is 9.8m/s.

Time = 5s

Force exerted to move the block = 200N

Force exerted by friction = 50N

Resultant Force = (200 - 50)N

                          = 150N

Now applying the force equation, F = m.a, to find out a.

                          $F = m.a\\150 = 50a\\a = \frac{150}{50}\\a = 3m/s^2$

Now using the first equation of motion, $v = u + at$ where u = 0m/s and t = 5s.

We get,

                          $v = u + at\\v = 0 + 3*5\\v = 15m/s$

The speed of the block after 5s is 15m/s.