When some unstable atoms break up, they release a tremendous amount of …………………… energy.
- Achemical
- Bpotential
- ✓nuclear
- Dmechanical
Answer: C.
View full solution →Question types
Work and Energy question types
128 questions across 10 question groups — pick any mix to generate a Science paper with step-by-step answer keys.
128
Questions
10
Question groups
5
Question types
01
Write the Correct Alternative.
24 Q→02Find the odd one out.
3 Q→03Write the following Statement Is True Or False. & Write True Statement.
10 Q→04Answer the following in one sentece.
39 Q→05Name The Following.
7 Q→06Distinguish Between.
2 Q→07complete the Graph/Table.
5 Q→08Answer the following question.
25 Q→09Give Scientific Reason.
6 Q→10Answer the following question.
7 Q→Sample Questions
Work and Energy questions
One sample from each question group in this chapter. Select any group above to see the full set with answer keys.
The work done by a force is said to be …………………… when the applied force does not produce displacement.
- Apositive
- Bnegative
- ✓zero
- Dnone of these
Answer: C.
View full solution →$1 kWh =$ …………………… joules.
- A$3.6 \times 10^3$
- ✓$3.6 \times 10^6$
- C$6.3 \times 10^6$
- D$6.3 \times 10^3$
Answer: B.
View full solution →…………………… is the commercial unit of power.
- Akilowatt second
- Bdyne
- ✓kilowatt
- Derg
Answer: C.
View full solution →1 hp = ………………….. .
- A476 watts
- ✓746 watts
- C674 watts
- D764 watts
Answer: B.
View full solution →A stretched spring, A rock rolling downhill, A bullet fired from gun.
A stretched spring, A body placed in at some height, A bullet fired from gun.
Work, Energy, Power, Force.
Kinetic energy has formula – $mv^2$
View full solution → The SI unit of work is newton.
The CGS unit of energy is dyne.
The kilowatt hour is the unit of energy.
Power is a scalar quantity.
Write the formula : Power
Write the formula : Force
Write the formula : Work
Write the formula : Potential energy
Write the formula : Kinetic energy
Various forms of energy
The relationship between 1 joule and 1 erg.
An example where force acting on an object does not do any work.
Two types of mechanical energy.
SI unit of energy.
Work and Energy:
Work and Power:
In physics, ………….. is the rate of doing work or, i.e., the amount of energy transferred or converted per unit time. In the International System of Units, the unit of power is the ………….. equal to one ………….. per second.
Power is a ………….. quantity that requires both a change in the physical system and a specified time interval in which the change occurs. But more ………….. is needed when the work is done in a shorter amount of time.
………….. energy and ………….. done are the same thing as much as ………….. energy and work done are the same thing. Potential energy is a state of the system, a way of ………….. energy as of virtue of its configuration or motion, while ………….. done in most cases is a way of channeling this energy from one body to another.
………….. is the measure of energy transfer when a force (F) moves an object through a ………….. (d). So when ………….. is done, energy has been transferred from one energy store to another, and so: energy transferred = ………….. done. Energy transferred and work done are both measured in ………….. (J)
Transformation of energy
![]()
https://api.studentbro.in/NCERTSOLUTION//wp-content/uploads/2021/01/Maharashtra-Board-Class-9-Scienc..." alt="Maharashtra Board Class 9 Science Solutions Chapter 2 Work and Energy 17" width="600" height="" srcset=" 604w, 300w" sizes="(max-width: 604px) 100vw, 604px" />
Transformation of energy
![]()
https://pg-data.sgp1.digitaloceanspaces.com/chapter_wise/15898/Q6.png" alt="Image" width="450" height="" />
Ravi applied a force of 10 N and moved a book 30 cm in the direction of the force. How much was the work done by Ravi? (Ans: 3 J)
The velocity of a car increase from 54 km/hr to 72 km/hr. How much is the work done if the mass of the car is 1500 kg? (Ans. : 131250 J)
If the energy of a ball falling from a height of $10$ metres is reduced by $40$ %, how high will it rebound? (Ans : $6\ m$)
View full solution →An electric pump has $2$ kW power. How much water will the pump lift every minute to a height of $10\ m$?
(Ans : $1224.5\ kg$)
View full solution →(Ans : $1224.5\ kg$)
1. Take two aluminium channels of different lengths.
2. Place the lower ends of the channels on the floor and hold their upper ends at the same height.
3. Now take two balls of the same size and weight and release them from the top end of the channels. They will roll down and cover the same distance.
2. Place the lower ends of the channels on the floor and hold their upper ends at the same height.
3. Now take two balls of the same size and weight and release them from the top end of the channels. They will roll down and cover the same distance.
Questions
1. At the moment of releasing the balls, which energy do the balls have?
2. As the balls roll down which energy is converted into which other form of energy?
3. Why do the balls cover the same distance on rolling down?
4. What is the form of the eventual total energy of the balls?
5. Which law related to energy does the above activity demonstrate? Explain.
Work done on an artificial satellite by gravity is zero while moving around the earth.
An exploding firecracker lights up as well as makes a sound.
Wind can move the blades of a windmill.
A stretched rubber band when released regains its original length.
Flowing water from some height can rotate turbine.
How is work calculated if the direction of force and the displacement are inclined to each other?
Explain the relation between, the commercial and SI unit of energy.
When can you say that the work done is either positive, negative or zero?
Derive the expression for potential energy.
Write effects of the following : Force
Generate a Work and Energy paper free
Pick question groups from the list above, set marks and difficulty, and export a branded PDF with step-by-step answer keys. First 3 chapters free — no signup.