A stone of mass 0.1 kg is thrown vertically upwards. Give the magnitude and direction of the net force the stone during it upward?
Answers
Answer:
) In all three cases i.e. upwards, downwards and at highest point the only force acting on stone is gravitational force. At any point, acceleration due to gravity always acts downwards with magnitude g = 9.8 m/s^2. ... Hence, force of 1 N in downwards direction will act on stone in all 3 conditions. Hope that is useful
Answer:
a) Here, m = 0.1 Kg,
a=g=10m/s
2
Net force, F=ma=1N
This force acts vertically downwards.
(b) When the train is running at a constant velocity, its acceleration =0, No force acts on the stone due to this motion.
Therefore, force on the stone F= weight of stone=mg=0.1×10=1.0N
This force also acts vertically downwards.
(c) When the train is accelerating with 1 m/s
2
,
an additional force F
′
=ma=0.1×1=0.1N acts on the stone in the horizontal direction.
But once the stone is dropped from the train,
F' becomes zero and the net force on the stone is F=mg=0.1\times 10=1.0N, acting vertically downwards.
(d) As the stone is lying on the floor of the train, its acceleration is the same as that of the train.
force acting on stone, F=ma=0.1×1=0.1N
This force is along the horizontal direction of motion of the train.
Note that in each case, the weight of the stone is being balanced by the normal reaction.