Laws Of Motion Question 189
Question:A block of metal weighing 2 kg is resting on a frictionless plane. It is struck by a jet releasing water at a rate of 1 kg/sec and at a speed of 5 m/sec. The initial acceleration of the block will be[MNR 1979]
Options:
A) $ 2.5m/{{\sec }^{2}} $
B) $ 5.0m/{{\sec }^{2}} $
C) $ 10m/{{\sec }^{2}} $
D) None of the above
Show Answer
Answer:
Correct Answer: A
Solution:
Force on the block F $ =u\ ( \frac{dm}{dt} )=5\times 1=5\ N $
$ \therefore$ Acceleration of block a $ $=$\frac{F}{m}$= $\frac{5}{2}$=$2.5\ m/s^{2} $
