(English Medium) ICSE Class 10 - CISCE Question Bank Solutions

What are the advantages and disadvantages of using solar cells for producing electricity?

Define an Inclined plane.

A block of mass 30 kg is pulled up a slope, as shown in diagram with a constant speed, by applying a force of 200 N parallel to slope.
A and B are initial and final positions of block.

(i) Calculate the work done by force in moving the block from A to B.
(ii) Calculate P.E. gained by block. [g=10ms^-2]

(i) A 200g ball is thrown vertically upward with an initial velocity of 30 ms^-1. Draw a velocity-time graph for the motion of ball.
(ii) How long will the ball take to reach the highest point?
(iii) What will be the kinetic energy of ball, when it returns to the starting point, neglecting the air resistance?
(iv) What will be the potential energy of ball at highest point?

A truck driver can load oil drums into the back of the truck by pushing them up a sloping plank, or by lifting them directly. Each drum has a mass of 80 kg, the plank is 3 m long, and the back of the truck is 0.8 m above the ground.

(i) How much force would be needed to lift a drum into the truck directly/without using the plank? (Take g = 10 m/s²)

(ii) How much energy would be required in lifting the drum into the truck without the plank?

(iii) If the force needed to push the drum up the plank is 300 N, why is this less than the answer to part (i)?

(iv) When the truck is loaded, the driver drives off. List the major energy changes that take place in moving the truck.

(v) The driver has to stop at the factory gates. What happens to the kinetic energy of the truck?

A man can open a nut by applying a force of 150 N by using a lever handle of length 0.4 m. What should be the length of the handle if he is able to open it by applying a force of 60 N?

Calculate the work done when:
A 5 kg weight is lifted 10 m vertically. (g = 9.8 m/s²)

A force is applied on a body of mass 20 kg moving with a velocity of 40 ms⁻¹. The body attains a velocity of 50 ms⁻¹ in 2 seconds. Calculate the work done by the body.

The work done by the heart is 1 Joule per beat. Calculate the power of the heart if it beats 72 times in one.

How long should an electric motor, of power 2 H.P. operate, so as to pump 5 m³ of water from a depth of 15m. [Take g = 10 N kg⁻¹]

How do you define force? What are the forces acting on a man standing in a lift? If the lift moves down with an acceleration of 2 ms⁻², what is the net force on the man if his mass is 50 kg?

A coolie is pushing a box weighing 1500 N up an inclined plane 7.5 m long on to a platform, 2.5 m above the ground.
(i) Calculate the mechanical advantage of the inclined plane. (ii) Calculate the effort applied by the coolie.
(iii) In actual practice, the coolie needs to apply more effort than what is calculated. Give one reason why you think the coolie needs to apply more effort.

An electric motor of power 100 W is used to drive the stirrer in a water bath. If 50% of the energy supplied to the motor is spent in stirring the water. Calculate the work done on the water in one minute.

The weights of two bodies are 2.0 N and 2.0 kgf respectively what is the mass of each body?

A girl of mass 40 kg runs a height of 80 stairs, each 25 cm high with a load of 20 kg on her head in 25 sec. If g is 10 m/s², find:
(i) Gravitational force acting on the girl.
(ii) Work done by her.
(iii) Useful work done by her.
(iv) Her power in watt.

A water pump raises 50 kg of water through a height of 25 m in 5s. Calculate the power supplied by the pump (Take: g = 10 N kg⁻¹).

An electric motor pump is 60% efficient and is rated 2.5 H.P. Calculate the maximum load it can lift through a height of 10m in 8 sec. (1 H.P. = 750 W).

What is a machine?

Name a machine which can be used to multiply force and change the direction of force applied.

Light of different colours is deviated through different angles by a prism. Explain the reason.