Question

Chapter :- Force and Law of Motion
with a velocity of 36 km/h hits a wall
sec. Find the force exerted by the car on the
1. A car of mass 1000kg moving with a velocity of 36 kv
and comes to rest in 5 sec. Find the force exerted by th
wall.
v of mass 100g is at rest on a smooth surface. A force of 02 N
acts on it for 5 sec .Calculate distance travelled by the body.
3. A hammer of mass 500g moving at 50m/s,strikes a nail. The nail
hammer in a very short time of 0.01s. what is the force o
stops the hammer in a very short time of
the nail on the hammer.
​

Answer 1

Answer:

Explanation:

1. F = ma

= m(v-u) / t

Since m = 1000kg

u= 36km/h = 36*1000/60*60 = 10m/s

v = 0

t = 5s

=) F = 1000( 0-10) / 5

= 1000*-10/5

= - 2000 N

2. m=100g =0.1kg

F=2N  

t=5 sec

u =0m/s

using F=ma

        2 = 0.1 * a

        a= 2/0.1= 20m/s2

To find the distance travelled,

we use  

s =ut +1/2 at2

 =   0* 5 + 1/2 * 20 * 52

  =250m

3. m = 500g = 0.5 kg

v = 0 m/s

u = 50 m/s

t = 0.01 s

F = m(v-u) / t

F = 0.5 (50-0) / 0.01

F = 0.5 x 50 x 100 / 1

F = 2500 N

Force of nail = 2500 N