Subject: Physics (Ch # 6,7) Class: IX
Total Marks: 12
1) An ideal system gives the output:
(a) 50% (b) 70% (c) 80% (d) 100%
2) A ball is thrown vertically upward. Its velocity
at the highest point is:
(a) -10 ms-1 (b) zero (c) 10 ms-2 (d) none of them
3) Which one of the following
converts light energy into electrical energy? (Board 2014)
(a) Electric
bulb (b) Electric generator (c) Photocell (d) Electric
cell
4) SI unit of pressure is the pascal, which is equal to:
(a) 104 Nm-2 (b) 1 Nm -2
( c) 102 Nm-2 (d) 103 Nm-2
5) The relation between the coefficient of linear
expansion and volume expansion is(Board 2015)
(a) a = 3b (b) b = 3a (c) a = 3/ b (d) b = 3/a
6) The work done will be zero when the angle between
the force and the distance is:
(a)
45o (b) 60o (c) 90o (d) 180o
7) Atmospheric pressure
acts in:
(a) Upward
direction (b) Downward direction (c) Opposite to force (d) All direction
8) Unit of strain is:
(a) Nm-2 (b) Nm (c) N (d) No unit
10) Which property can
determine by Archimedes' principle:
(a) Vapour
pressure (b) Density (c) Compressibility (d) Elasticity
11) Fossil fuels are
usually:
(a) Carbon dioxide (b) Hydrogen (c) Hydrocarbons (d) Carbon monoxide
12) Name a device that converts mechanical energy into electrical energy.
(a) Electrical motor (b) generator (c) wind turbines (d) Both b & c
Subjective Part
Subject: Physics Class:
IX Total Marks: 48
2. Answer All Questions 2 × 15 = 30
i.
Write the
uses of Wind Energy.
ii. What is geothermal energy?
iii.
How energy
is obtained from biomass?
iv.
How does
electricity production from fossil fuels?
v. Calculate the density of 5 liters of water having a mass of 5 Kg.
vi.
What measures
should be taken to save energy in our houses?
vii.
What is
meant by the efficiency of a system? Write its formula.
viii.
What are the
environmental issues associated with energy?
ix.
What is the
principle of floatation?
x. Under what conditions do an object sinks and floats
on the surface of the water?
xi.
State Pascal’s law and give its four applications in our daily life?
xii.
Why does a
piece of stone sink in water but a ship with a huge weight floats?
xiii.
An iron
sphere of mass 5 kg, the density of iron is 8200 kgm-3 Find the volume.
xiv.
What is meant by interconversion of
energy?
xv.
A girl carries a 10 kg bag upstairs to a height of 18
steps, each 20 cm high. Calculate the amount of work she has done to carry the
bag.
Note: Attempt All questions. (2×10=20)
1. (a ) What is Hooke’s Law? What is meant by
elastic limit? (5)
(b) A 50 kg man moved 25 steps up in 20
seconds. Find his power, if each step is 16 cm high.
2. (a) what are renewable
Energy sources write their name and explain any two of them. (5)
(b) The head of a pin is a square of a side 10 mm. Find the pressure on it due to a force of 20 N.
