HSC Science (General) ११ वीं कक्षा - Maharashtra State Board Question Bank Solutions

Justify the statement, “Work and energy are the two sides of a coin.”

Answer the following question.

From the terrace of a building of height H, you dropped a ball of mass m. It reached the ground with speed v. Is the relation mgh = `1/2"mv"^2` applicable exactly? If not, how can you account for the difference? Will the ball bounce to the same height from where it was dropped?

100 cells each of emf 5 V and internal resistance 1 Ω are to be arranged so as to produce maximum current in a 25 Ω resistance. Each row contains equal number of cells. The number of rows should be ______.

Choose the correct alternative.

Five dry cells each of voltage 1.5 V are connected as shown in the diagram

What is the overall voltage with this arrangement?

Give reason/short answer.

In the given circuit diagram two resistors are connected to a 5V supply.

Calculate potential difference across the 8Ω resistor.

Give reason/short answer.

In the given circuit diagram two resistors are connected to a 5V supply.

A third resistor is now connected in parallel with 6Ω resistor. Will the potential difference across the 8Ω resistor the larger, smaller, or the same as before? Explain the reason for your answer.

Answer the following question.

State the law of conservation of linear momentum. It is a consequence of which law? Give an example from our daily life for the conservation of momentum. Does it hold good during the burst of a cracker?

Solve the following problem.

A lighter object A and a heavier object B are initially at rest. Both are imparted with the same linear momentum. Which will start with greater kinetic energy: A or B or both will start with the same energy?

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)?

Answer the following question.

Are freezing point and melting point same with respect to change of state? Comment.

Define Sublimation.

Define Triple point.

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.