Advertisements
Advertisements
प्रश्न
उत्तर
K.E = `1/2` mv2
K.E = `1/2`(2) (20)2
or K.E = 400 J
Thus K.E is 400J
APPEARS IN
संबंधित प्रश्न
A pair of bullocks exerts a force of 140 N on a plough. The field being ploughed is 15 m long. How much work is done in ploughing the length of the field?
Explain briefly why the work done by a fielder when he takes a catch in a cricket match is negative.
The S.I. unit of work is
.A man raises a box of mass 50kg to a height of 2m in 20s, while another man raises the same box to the same height in 50s. Compare:
(i) the work done, and
(ii) the power developed by them.
A boy weighing 25 kgf climbs up from the first floor at height 3 m above the ground to the third floor at height 9m above the ground. What will be the increase in his gravitational potential energy? (Take g = 10 N kg -1)
State the law of conservation of energy.
What are the units of (a) work, and (b) energy?
Name the physical quantity whose SI unit is Nm.
Why does a spanner have a long handle?
No work is done by a man moving on a horizontal road while carrying a box on his head. Explain.
Name the physical quantity associated with the 'rate of doing work'.
Define the term work. Name the CGS and SI unit of work.
Fill in the boxe to show the corresponding energy transformation.
Name two places in India where electricity is generated from nuclear power plants.
A car is accelerated on a levelled road and attains a velocity 4 times of its initial velocity. In this process the potential energy of the car
