Physics – Class 11 Mock Test 4

10%

Question 1 of 10

1. A spring is stretched by a length x, then the potential energy stored in it changes by 0.5*k*x², where k is the spring constant.

True

False

Question 1 of 10

Question 2 of 10

2. The elastic potential energy varies linearly with displacement.

True

False

Question 2 of 10

Question 3 of 10

3. What is the SI unit of variable force?

Newtons

Joules

Mole

Ampere

Question 3 of 10

Question 4 of 10

4. A machine gun fires 360 bullets per minute. Each bullet has a mass of 5 grams and travels at 600 m/s. What is the power of the gun? (Assume no loss of energy and 100% power transmission)

1800 W

300 W

600 W

900 W

Question 4 of 10

Question 5 of 10

5. For a body of mass “m” on a rough inclined plane with a constant but arbitrary coefficient of friction as shown in the figure, what is the angle of repose if the net downward force is donated as “F”. Let “g” be the acceleration due to gravity and “u” be the coefficient of friction.

sin θ

cos θ

tan θ

cot θ

Question 5 of 10

Question 6 of 10

6. What kinetic energy should be imparted to an object of mass “m” to raise it to a height of 1000 meters? (Take g = 10 m/s²)

100m J

10m J

10000m J

1000m J

Question 6 of 10

Question 7 of 10

7. Which of the following statements are true?

Energy can neither be created nor destroyed

Energy cannot be created but only destroyed

Energy can be created and destroyed

Energy cannot be destroyed but only created

Question 7 of 10

Question 8 of 10

8. A body of mass 40 Kg covers a distance of 50 m in 5s starting from rest under the influence of a force. What is the work done by the force on the body?

20000 J

-8000 J

8000 J

800 J

Question 8 of 10

Question 9 of 10

9. When a person intakes 3000 kcal of food, he is able to do work requiring energy of 2500 kcal. This means that the human body destroys a fraction of energy obtained from food.

False

True

Question 9 of 10

Question 10 of 10

10. Which of the following is true?

Potential energy increases as altitude increases

Potential energy first increases and then decreases as altitude increases

Potential energy decreases as altitude increases

Potential energy first decreases and then increases as altitude increases

Question 10 of 10