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प्रश्न
1 J = ______ calorie.
उत्तर
1 J = 0.24 calories.
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संबंधित प्रश्न
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A sailboat is moving due to wind energy.
Name a common device where a gear train is used
In which of the following cases, is work being done?
(i) A man pushing a wall.
(ii) a coolie standing with a load of 12 kgf on his head.
(iii) A boy climbing up a staircase.
Differentiate between energy and power.
A vessel containing 50 kg of water is placed at a height 15 m above the ground. Assuming the gravitational potential energy at ground to be zero, what will be the gravitational potential energy of water in the vessel? (g = 10 m s-2)
A bullet of mass 0.5 kg slows down from a speed of 5 m s-1 to that of 3 m s-1. Calculate the change in kinetic energy of the ball.
State two advantage of producing hydroelectricity.
State the SI unit of work.
A person of mass 50 kg climbs a tower of height 72 metres. Calculate the work done. (g = 9.8 m s−2).
What happens to the work done when the dispacement of body is at right angles to the direction of force acting on it? Explain your answer.
Name the physical quantity whose SI unit is Nm.
State the conditions of equilibrium for a rigid body.
Complete the following sentences:
Joule is the unit of .......
Name the type of energy possessed by a
(i) stretched catapult (ii) hot iron
(iii) wound up clock
Why is less effort needed to lift a load over an inclined plane as compared to lifting the load directly?
What should be the characteristic of a source of energy?
(i) A 200g ball is thrown vertically upward with an initial velocity of 30 ms-1. Draw a velocity-time graph for the motion of ball.
(ii) How long will the ball take to reach the highest point?
(iii) What will be the kinetic energy of ball, when it returns to the starting point, neglecting the air resistance?
(iv) What will be the potential energy of ball at highest point?
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A donkey is carrying a load on its back.
Work done by this force at any instant is ______.
