Dedicated To My Son Mohammad Irtaza Zain Code 5054 Turn Over

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Test (Unit 6)Name:…………………………………………………………………………………………………………Paper: Physics

Time Allowed: 40Minutes Code 5054 Maximum Marks: 25

Date: ………………………………This Document Consists Of 4 Printed Pages. Class: C1

Theory Section [Total 20Marks]Q1. (a) State the meanings of the terms work and power. Also mention their SI units.

………………………………………………………………………………………………………

………………………………………………………………………………………………………

…………………………………………………………………………………………………...[4]

(b) The front of a lorry may be regarded as a flat vertical plane of area 7.0m2.The average

pressure due to air resistance; perpendicular to the front of lorry is 400 N/m2, when the speed of

lorry is 25m/s2.

Calculate the force, due to air resistance, acting on the front of lorry when it is travelling at

25m/s.

Force=..............................................N [2]

(c) Calculate the power dissipated in overcoming the air resistance when the lorry is travelling at25m/s.

Power=……………………………W [3]

………………………………………………………………………………………………………

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Dedicated To My Son Mohammad Irtaza Zain Code 5054 Turn Over

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(d) What happens to the energy lost by the lorry in maintaining its speed against this resistance?

………………………………………………………………………………………………………

………………………………………………………………………………………………… [2]

[Total 11]

Q2 An empty lift counter balanced by heavy piece of metal. Some people of combined mass

350kg enter the lift and operate it. The lift rises 50m in 60s.

Calculate

(a) The work done in raising the people,

Work done=………………….J [2]

(b) The power required to do this.

Power=……………………W [2]

[Take the weight of 1kg to be 10N]

[Total 4]

Q3 A boy of mass 50kg runs up a flight of steps in 40s. There are 20 steps each of 0.25m.

Calculate

(a) The weight of the boy.

Weight=……………………N [1]

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Dedicated To My Son Mohammad Irtaza Zain Code 5054 Turn Over

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(b) The gain in potential energy.

Potential Energy=…………………………..J [2](c) The power developed.

Power=………………………W [2]

[Total 5]

MCQ Section: [Total 5 Marks]

Q1 A 40Wflourescent lamp turns half the electrical energy it uses into light energy.

How much light energy does it give out in 10 s?

A 8J B 20J C 200J D 400 J

Q 2 A boy pushes a toy cart along a level road and the lets it go. As the cart is slowing down, the

biggest energy change is from

A chemical to heat B chemical to kinetic

C kinetic to chemical D kinetic to heat

Q3 A ball of mass 0.2kg is thrown to a height of 15m. What is the change in its gravitational

potential energy? (g=10N/kg)

A 0.3 J B 3.0 J C7.5 J D 30 J

Q4 Which of the following quantities is calculated by multiplying force by distance?

A Acceleration B Power C Velocity D Work

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MCQ Answer Sheet

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Q5 What are the energy changes in hydroelectric power production?

A electrical potential kinetic

B kinetic electrical potential

C potential electrical kinetic

D potential kinetic electrical

5 A B C D

4 A B C D

3 A B C D

2 A B C D

1 A B C D

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