HSC Science (Computer Science) ११ वीं कक्षा - Maharashtra State Board Question Bank Solutions for Physics

Solve the following problem.

The figure below shows a block of mass 35 kg resting on a table. The table is so rough that it offers a self-adjusting resistive force 10% of the weight of the block for its sliding motion along with the table. A 20 kg wt load is attached to the block and is passed over a pulley to hang freely on the left side. On the right side, there is a 2 kg wt pan attached to the block and hung freely. Weights of 1 kg wt each, can be added to the pan. Minimum how many and maximum how many such weights can be added into the pan so that the block does not slide along the table?

Ten identical masses (m each) are connected one below the other with 10 strings. Holding the topmost string, the system is accelerated upwards with acceleration g/2. What is the tension in the 6th string from the top (Topmost string being the first string)?

Explain: ‘How is a rainbow formed’?

Define coefficient of restitution.

Answer the following question.

Obtain its value for an elastic collision and a perfectly inelastic collision.

Answer the following question.

Discuss the following as special cases of elastic collisions and obtain their exact or approximate final velocities in terms of their initial velocities.

1. Colliding bodies are identical.
2. A very heavy object collides on a lighter object, initially at rest.
3. A very light object collides on a comparatively much massive object, initially at rest.

Answer the following question.

A bullet of mass m₁ travelling with a velocity u strikes a stationary wooden block of mass m₂ and gets embedded into it. Determine the expression for loss in the kinetic energy of the system. Is this violating the principle of conservation of energy? If not, how can you account for this loss?

Solve the following problem.

A ball of mass 100 g dropped on the ground from 5 m bounces repeatedly. During every bounce, 64% of the potential energy is converted into kinetic energy. Calculate the following:

1. Coefficient of restitution.
2. The speed with which the ball comes up from the ground after the third bounce.
3. The impulse was given by the ball to the ground during this bounce.
4. Average force exerted by the ground if this impact lasts for 250 ms.
5. The average pressure exerted by the ball on the ground during this impact if the contact area of the ball is 0.5 cm².

Solve the following problem.

A spring ball of mass 0.5 kg is dropped from some height. On falling freely for 10 s, it explodes into two fragments of mass ratio 1:2. The lighter fragment continues to travel downwards with a speed of 60 m/s. Calculate the kinetic energy supplied during the explosion.

Solve the following problem.

A marble of mass 2m travelling at 6 cm/s is directly followed by another marble of mass m with double speed. After a collision, the heavier one travels with the average initial speed of the two. Calculate the coefficient of restitution.

Answer the following question in detail.

State the conditions under which a rainbow can be seen.

Answer the following question in detail.

Explain the formation of a primary rainbow. For which angular range with the horizontal is it visible?

Answer the following question in detail.

Explain the formation of a secondary rainbow. For which angular range with the horizontal is it visible?

Answer the following question in detail.

Is it possible to see primary and secondary rainbow simultaneously? Under what conditions?

Answer briefly.

What is Doppler effect?

State the expression for apparent frequency when listener is stationary and source is moving towards the listener.

Answer briefly.

State the expression for apparent frequency when the source is stationary and the listener is

1. moving towards the source
2. moving away from the source

Answer briefly.

State the expression for apparent frequency when source of sound and listener are

1. moving towards each other
2. moving away from each other

Solve the following problem.

A police car travels towards a stationary observer at a speed of 15 m/s. The siren on the car emits a sound of frequency 250 Hz. Calculate the recorded frequency. The speed of sound is 340 m/s.

The sound emitted from the siren of an ambulance has a frequency of 1500 Hz. The speed of sound is 340 m/s. Calculate the difference in frequencies heard by a stationary observer if the ambulance initially travels towards and then away from the observer at a speed of 30 m/s.