Question

A steel ball of mass 15.0 g is fired from the small canon onto a wooden plank of mass
350 that is placed horizontal to the ground. The wooden plank slides to the distance of
7.00 m after collision with ball. Find the velocity of the ball before impact with the plank,
considering the value of coefficient of friction as 0.5.
(a) 178.25 m/s
(b) 185.37 m/s
(c) 225.35 m/s
(d) 201.54 m/s
​

Answer 1

Explanation:

Correct option is

A

281ms

−1

After collision initial K.E of combined mass =3×10×0.1

=3J

⇒

2

1

×3×v

2

=3

v=

2

m/s

conserving momentum

15×v=3000×

2

v=281m/s