Advertisements
Advertisements
Question
Write scientific reasons.
When we drop a feather and a stone at the same time from a height the stone reach the earth faster than a feather.
Advertisements
Solution
- When we drop a feather and a heavy stone at the same time from a height, the feather experiences a buoyant force and a frictional force due to air and therefore floats and reaches the ground slowly.
- But the buoyant and frictional forces on the stone are much less than the weight of the stone and does not affect the speed of the stone much.
- Hence, when we drop a feather and a stone at the same time from a height, the stone reach the earth faster than a feather.
APPEARS IN
RELATED QUESTIONS
A ball is thrown vertically upwards with a velocity of 49 m/s. Calculate
- the maximum height to which it rises.
- the total time it takes to return to the surface of the earth.
A stone is thrown vertically upward with an initial velocity of 40 m/s. Taking g = 10 m/s2, find the maximum height reached by the stone. What is the net displacement and the total distance covered by the stone?
What is the usual value of the acceleration due to gravity of earth ?
Why does a sharp knife cut objects more effectively than a blunt knife ?
Name the force which stops you falling through the floor.
The value of acceleration due to gravity of earth :
Choose one or more correct alternatives.
Which of the forces involved in dragging a heavy object on a smooth, horizontal surface, have the same magnitude?
- The horizontal applied force
- gravitational force
- reaction force in vertical direction
- force of friction
The acceleration produced in a body by a force of given magnitude depends on
A force of 10 N acts on a body of mass 5 kg. Find the acceleration produced.
Figure shows the velocity-time graph of a particle of mass 100 g moving in a straight line. Calculate the force acting on the particle.
(Hint : Acceleration = Slope of the v-t graph)
What is escape velocity?
In vacuum, all freely falling objects have the same force. Is it true?
Explain why:
Objects fall to the earth.
The free fall of an object is possible only in ______.
Right or wrong sentence:
The value of gravitational acceleration at the centre of earth is zero.
Write the acceleration due to gravity value on the surface of Earth.
Distinguish between:
Universal gravitational constant – Gravitational acceleration of earth.
