Mechanical Energy

Q.

State the Law of Conservation of Mechanical Energy. What is the essential condition for it?

Q.

Does the transfer of energy take place when you push a huge rock with all your might and fail to move it? Where is the energy you spend going?

Q.

The total mechanical energy of a system is conserved if the forces that act on it are ____.

Q.

Name the energy transformations taking place in an arrow released from a bow.

Q.

Hammer drives a nail into wood only when lifted and then struck. give a reason for the same.

Q.

A raised hammer possesses _______.

Q. What is the relationship between the kinetic energy($K$), potential energy($P$) and total energy($E$) of a system?

1. $K=P+E$
2. $P=K+E$
3. $E=P+K$
4. $E=PK$

Q. define the law of conservation of mechanical energy.

Q.

How is electrical energy generated in a hydroelectric powerplant?

Q.

What type of energy is stored in the following cases?

a) A stretched rubber band

b) A compressed spring

c) An extended spring (or slinky)

d) An object at a certain height

e) A stretched bow

Q. The conservation principle of mechanical energy requires that

1. There should be no external forces
2. The motion should be restricted to the gravitational force
3. The acceleration should be zero
4. The force should be conservative

Q. Which is best used as a sound absorbing material in partition walls

Q. In a hydroelectric power plant ______ energy is converted into _______ energy.

1. Chemical into electrical
2. Chemical into mechanical
3. Mechanical into electrical
4. Electrical into mechanical

Q.

A hydroelectric power plant uses the transformation of ______ energy to ______ energy to generate electricity.

Q. If $484J$ of energy is spent in increasing the speed of a wheel from $60rpm$ to $360rpm$, the $M.I$ of the wheel is

1. $1.2kg{m}^2$
2. $0.7kg{m}^2$
3. $1.6kg{m}^2$
4. $0.3kg{m}^2$

Q.

Energy possessed by a phone ringing on the table.

Q. What is mechanical energy?

Q.

Two spherical balls of the same radius, but of different masses, are dropped at the same time from the top of a tower $19.6\mathrm{m}$ high. When they are $1.6\mathrm{m}$ above the ground, the balls will possess the same

1. K.E.

2. P.E.

3. momentum

4. total energy

Q. Select the best definition of mechanical energy?

1. Energy possessed by an object due to its location or motion
2. Energy possessed by an object due to its temperature
3. Energy possessed by an object due to its age
4. Energy of an object due to its concentration
5. Energy possessed by an object due to its magnetic property

Q. A body is falling freely under the action of gravity alone in vacuum. Which of the following quantities remain constant during the fall?

1. Kinetic energy
2. Potential energy
3. Total mechanical energy
4. Total linear momentum

Q. Name the form of mechanical energy, which is put to use for doing work.

1. Kinetic energy
2. Potential energy
3. Electric energy
4. Heat energy

Q. Mechanical Energy is conserved under?

1. Conservative system of forces
2. disipative forces
3. (A) and (B)
4. none of these

Q. Can any object have mechanical energy even if its momentum is zero ?
Explain.

Q. Which of the following has both kinetic energy and potential energy ?

1. A flying bird
2. A bent bow about to shoot an arrow
3. An athlete running at full speed
4. None of the above

Q. Kinetic energy and potential energy are the two forms of

1. thermal energy
2. nuclear energy
3. mechanical energy
4. chemical energy

Q.

In hydroelectric plant, when flowing water moves the turbine ________ energy transforms into ________ energy.

Q.

What are two types of mechanical energy?

Q. What is meant by mechanical energy? Explain in detail

Q. A body of mass $15kg$ is raised from certain depth. If the work done in raising it by $10m$ is $1620J$, its velocity at this position is$(g=10{ms}^{-2})$:

1. ${2ms}^{-1}$
2. ${4ms}^{-1}$
3. ${1ms}^{-1}$
4. ${8ms}^{-1}$

Q. A flying aeroplane has:

1. only kinetic energy
2. only potential energy
3. both potential and kinetic energy
4. none of these