Work And Energy Flashcards
A boy holds a mass on his stretched hand.then
Muscular energy is used
The energy possessed by an oscillating pendulum of a clock is
Mechanical energy
What is the commercial unit of energy ?
KW h.
When speed of the moving object is doubled its
Kinetic energy is increased to four times
A ball is thrown vertically upwards. It’s velocity keeps on decreasing. What happens to its K.E when its reaches the maximum height ?
K.E will be zero
If work is done at a faster rate,then
Power is more
Work done by a body can be
Negative,positive,zero
The work done is zero if
The body shows a displacement in perpendicular direction of force applied.
Power =
Work/time
A spring is compressed the P.E of the compressed spring
Increases
The potential energy of a man is maximum when
He is standing
SI unit of power is
Watt
Number of joules contained in 1KW h
3.6 X 10⁶
Work done is said to be positive when a force causes displacement.
In the same direction as the displacement of the object
The rate of work done is called
Power
What is the energy possessed by an object due to its motion
Kinetic energy
The capacity of a body to perform work is called
Energy
A stone is tied to a string and whirled in a circular path. The work done by the stone is
Zero
Potential energy of a body is depends on its
Position
Work done by friction
Decrease K.E of the body
Water stored in dam possesses
Potential energy
P.E of a spring increases when it is in the state of
Compression and expansion
When a body falls freely towards the earth, then it’s total energy
Remains constant
Momentum =
Mass X velocity
K.E =
1/2 mv²
P.E =
mgh
m1 X v1 =
m2 X v2
