Practice Questions

Work, Energy and Power

Bronze Questions

A uniform horizontal force of 80 N acts on a body such that the body moves a distance of 4 m in the line of action of the force. Find the work done on the body.
A uniform force of 80 N acts at 30 degrees to the horizontal on a body such that the body moves horizontally by a distance of 4 m. Find the work done on the body.
Calculate the energy of a 2 kg object being moved horizontally at a constant velocity of 10 m/s.

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Silver Questions

Calculate the energy of a 10 kg object being held stationary 5 m above the ground. If the object is released from rest, what is its potential energy when it hits the ground?
100 J of electrical energy is supplied to a 100 W light bulb every second. Of this, only 10 J is transferred to the surroundings as light energy. The rest, is transferred to the surroundings as heat energy. Calculate the efficiency of the light bulb.
A force of 3 N is applied to a spring. The spring stretches reversibly by 0.15 m. Calculate the spring constant.

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Gold Questions

A locomotive of mass 80 tonnes hauls a train of 12 coaches up an incline of 1 in 80. The rolling resistance to motion is 55 N/tonne. Each coach is of mass 20 tonne. If the speed is increased from 24 to 48 km/h in 600 m and the time taken is 30 seconds find:-
a) the change in the kinetic energy of the train
b) the total work done during this period
c) the average power developed
A spring requires a force of 100 N, gradually applied, to compress it 20 mm. Find the amount of compression when a 1.6 kg mass falls freely from rest on to the top of the spring through a height of 80 mm. The spring is initially unloaded.
A hammer of mass 30 kg is held in a horizontal position and then released so that it swings in a vertical circle of radius 1 m. What is the kinetic energy and speed of the hammer at its lowest point?

If at the lowest point it strikes and breaks a metal specimen and moves through an angle of 50obeyond the vertical before instantaneously coming to rest, how much energy has been absorbed by the specimen?

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AlAnoud AlYazeedi
29 April 2019 at 19:10
[Updated: 29 April 2019 at 19:11]

You have got enough practice questions for students to solve and I really like the fact that you divided the practice questions by difficulty ( bronze, silver, and gold ). Very creative and individualistic !! @_@

Arwa Al Shukairi
2 May 2019 at 20:09

Comment removed by the author

Amna Almarashda
2 May 2019 at 21:16

I must say it’s a great e-portfolio Adeoluwa however, it would have been even better if you have included a summary section, to sum up, all the information about the topic and you could have of included the video you did put in the pre-requisite section.

Arwa Al Shukairi
2 May 2019 at 21:22

Hi,

I personally think that information in your portfolio are distributed in a good way between the pages of your portfolio as you allocated a separate page for every part of the topic. The pre-requisite section almost covers all the things that the student should be aware of before getting into the topic. Also, the diagrams that you have included within the pages really helps get a better idea about what you are trying to explain and frequently asked section covers all the possible questions that they could think of.

Although you have added some practice example at the end of I think that having some questions within every page would have been better so that the student can check his understanding of the information mentioned in the page before moving into the next page as well as including video solutions trying to explain some problems which require more explanation. Having a summary section and adding some websites or books that the student can refer to when studying would have been a good idea.

Aiah Altayeb
3 May 2019 at 3:01

It was an excellent idea that you divided the questions by difficulty, however, I think it could have been better if you added video solutions to a few of the questions provided. In addition, to adding additional resources for the students to use.

Slyvn Omwenga
3 May 2019 at 23:07

This was very organised and easy to understand. Good job

Frances Peterson
3 May 2019 at 23:23

Hi Ade,

I think your practice questions are really useful, it's also great that you included questions of varying difficulty, so that students can make their way up towards the most difficult questions. It would have also been great if you had included some video solutions showing the step by step process of how to work out the answers to some of the questions.

Slyvn Omwenga
8 May 2019 at 16:03

Hey,

The layout of the presentation was very well put together hence making it easier for the learner to follow through without strain. The information provided in the pre-requisites page is very useful for the learner and it is very easy to understand from the way you have pit it.I was a good idea to separate the various sub-topics into different pages. This will make the learner go through the topic easily without any confusion. However, information provided was a lot and it would have been much better if you divide the notes into smaller paragraphs or rather write in point form. This would make it easier for the learner to scan through the notes if they are trying to reflect back on a specific point that may have been provided. However, the information provided was relevant and easy to understand. Also, dividing the questions in order of its difficulty was a very wise way of helping the learner challenge themselves further. Providing a link to their respective solutions is very helpful and also a good way tome sure he or she is not peeping at the solutions when making an attempt to complete the question on their own. Kudos!

On the other hand, it would have been extremely helpful if you provided a list of references for further information and also for additional resources

Ahmed Hasnain
8 May 2019 at 21:34

The fact that you have levelled out different difficulty ratings of the practise question was a wonderful and useful idea to users who want to skip the easy question to the hard ones, vice versa. The information flowed in most of the sections of your e-portfolio, the addition of colour was a very neat touch.

However you did not reference any of the sources used.