Question

A 20.0 kg mass moving at a velocity of + 3.0 m/s is stopped by a constant force of 15.0 N. How many seconds must the force act on the mass to stop it?

Answer 1

@shamim

Answer 2

Use
F=ma
15=20a
a=?

Answer 3

Now use
v=u-at
0=3-at
t=?

Answer 4

a=.75

Answer 5

3-2.25= .75 for t as well... or did i do something wrong?

Answer 6

Ok. C
v=u-at
0=3-0.75t
0.75t=3
t=3/0.75
t=?

Answer 7

t=4 thanks again!

Answer 8

U r most welcome!!!!!!!!!!