Question

1. Which force is being applied by a vendor when he is pushing the pushcart? *

Muscular force
Magnetic force
Friction
Electrostatic force
2. What will happen to the speed of a car when the driver applies brakes? *

Speed increases
Speed decreases
No change in speed
Change in direction
3. The pressure of the water at the bottom of the pond is _______ at the surface of the pond. *

higher than
lower than
same
either higher or lower
4. As we go to the higher altitude the atmospheric pressure ________. *

increases
remains same
cannot say
decreases
5. A dropper used to fill ink works because of *

air pressure
electrostatic pressure
friction
magnetic force
6. Pressure is *

Directly proportional to the area of contact
Directly proportional to the mass
Inversely proportional to the area of contact.
Inversely proportional to force.
7. Two boys exert force of 40 N and 60 N in opposite direction on an object. The resultant force is *

20 N
40N
100 N
240 N
8. Calculate the pressure produced by a force of 800 N acting on an area of 2.0 m2. *

400 N / m2
40 N / m2
800 N / m2
1600 N / m2
9. The pressure of a gas contained in a cylinder with a movable piston is 300 Pa. The area of the piston is 0.5 m2. Calculate the force that is exerted on the piston. *

600 N
150 N
1500 N
0 N
10. Which force always opposes motion? *

friction
electrostatic force
magnetic force
muscular force

Answer 1

1. Muscular force

2. Speed decreases

3. higher than

4. decreases

5. air pressure

6. Inversely proportional to the area of contact

7. 20 N

8. 400 N / m2

9. 150 N

10. friction

Step-by-step explanation:

1. During pushing the pushcart the person is required to use strength of his arms and legs muscles that will creat a force between the surfaces, hence the force used is muscular force.

2. The speed of car decreases while applying brakes because a friction is generated between the brakes and the wheel that reduces the kinetic energy of vehicle and decreases the speed of the vehicle.

3. The pressure of the water at the bottom of the pond is higher than at the surface of pond because water pressure increases with the depth of the water. Water pressure increases in the depth because weight of water over the body icreases as going deep.

4. At higher altitude the atomspheric pressure decreases because as the height in atmosphere increases the amount of air molecules decreases and so, less oxygen for breathing.

5. Air pressure allows the dropper to fill inks as dropper exerts a force on a surface of ink and due to the low pressure inside the dropper sucks up the liquid.

6. Pressure is defined as the perpendicular force exerted at the surface or it means force per unit area. Pressure is directly proportional to the force and inversely proportional to area of contact.

7. The boys exerts pressure in opposite direction on an object, hence the resultant force will be

resultant force = force 1 - force 2 = 60N−40N=20N.

8. pressure (P) is equal to force (F) per unit area (A)

P = F / A

= 800 / 2

= 400 N / m2

9. Pressure (P) = 300 Pa

Area of Cross-section (A) = 0.5 m²

Force = P × A

= 300 × 0.5

= 150 N

10. Friction is the force that is always applied against or opposite to the moving direction of an object. Friction is responsible to stop the movement of any moving object such as vehicles and sliding objects.

Hence, the correct option of the questions are:

1. Muscular force

2. Speed decreases

3. higher than

4. decreases

5. air pressure

6. Inversely proportional to the area of contact

7. 20 N

8. 400 N / m2

9. 150 N

10. friction