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1. CONCISE Physics - Middle School - 8

CHAPTERS

1. Matter

2. Physical Quantities and Measurement

3. Force and Pressure

4. Energy

5. Light Energy

6. Heat Transfer

7. Sound

8. Electricity

EXERCISES

1. Objective Questions

2. Short/Long Answer Questions

3. Numericals

Q1) Write true or false for each statement (a) The S.I unit of force is kg.

(b) A force always produces both the linear and turning motions.

(c) Moment of force = force perpendicular distance of force.

(d) Less force is needed when applied at a farther distance from the pivoted point.

(e) For a given thrust,pressure is more on a surface of large area.

(f) The pressure on a surface increases with an increase in the thrust on the surface.

(g) A man exerts same pressure on the ground whether he is standing or he is lying.

(h) It is easier to hammer a blunt nail into a piece of wood than a sharply pointed nail.

(i) The S.I unit of pressure is pascal.

(j) Water in a lake exerts pressure only at its bottom.

(k) A liquid exerts pressure in all directions.

(l) Gases exert pressure in all directions.

(m) The atmospheric pressure is nearly 105 pa.

(n) Higher we go, greater is the air pressure

Q4) Select the correct alternative

(a) SI. unit of moment of force is

N

N cm

kgfm

N m

(b) To obtain a given moment of force for turning a body, the force needed can be decreased by

applying the force at the pivoted point

applying the force very close to the pivoted point

Applying the force farthest from the pivoted point

none of the above

(c) The unit of thrust is

kgf

kg

g

m\ s^{-1}

(d) The unit of pressure is ...................

N x m

N m^{-2}

kgf m^2

(e) The pressure and thrust are related as

pressure = thrust

pressure = thrust x area

pressure= thrust /area

pressure = area/thrust

(f) A body weighing 5 kgf, placed on a surface of area 0.1 m2, exerts a thrust on the surface equal to

50 kgf

5kgf

50 kgf m^2

5 kgf m^{-2}

(g) The feet of lizards act like ..............................................................

moving pads

drilling pads

Suction pads

(h) Pressure exerted by a liquid is due to its ...................

Weight

Mass

Volume

Area

(i) Pressure inside a liquid increases with

Increase in depth

decrease in depth

decrease in density

(j) The atmospheric pressure at sea level is nearly

10 Pa

100,000 Pa

100 Pa

10,000 Pa

(k) Nose bleeding may occur at a high altitude because

The atmospheric pressure decreases

the oxygen content of atmosphere decreases

the atmospheric pressure increases

there are strong air currents at the high altitude

Q2) Fill in the blanks: (a) 1 kgf = ____ (nearly)

(b) Moment of force = _____ x distance of force from the point of turning.

(c) In a door, a handle is provided _____ from the hinges.

(d) The unit of thrust is __\.

(e) Thrust is the ______ force acting on a surface.

(f) Pressure is the thrust acting on a surface of _____ area.

(g) The unit of pressure is _\.

(h) Pressure is reduced if ______ increases.

(i) Pressure in a liquid _____ with the depth.

(j) The atmospheric pressure on earth surface is nearly _\.

Q3) Match the following:

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Biology

Mathematics

Physics

CONCISE Physics - Middle School - 8

Matter

Physical Quantities and Measurement

Force and Pressure

Energy

Light Energy

Heat Transfer

Sound

Electricity

Objective Questions

Short/Long Answer Questions

Numericals

Lido

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Race To Space

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