Question

ye krke dikhao tb mane tumhe ​

Answer 1

Answer:

mass of block = 250 g = 1/4 kg

weight of block = mg = g/4 kg

Normal force = weight = g/4 kg

force of friction = uN = 0.1*g/4 = g/40 N

= 10/40 = 1/4 N (taking g = 10ms^-2)

deceleration created = F/m = (1/4)/(1/4) = 1 ms^-2

initial speed = u = 40 cm/s = 0.4 m/s

a = -1 m/s^2

v= 0 m/s

now

v^2 = u^2 - 2as

u^2 = 2as

0.4*0.4 = 2*1*s

2s = 0.16

s= 0.08 m

now

work done = force x displacement

= 1/4*0.08 = 0.02 joule