JOIN ADRE 2.0 Telegram Group

NCERT Solutions for class 11 Physics | Chapter 5 - Laws of motion

Questions
1 A force of 20 N moves a body , in its direction throught a distance of 2 m . The work done by the force is
A 22 J
B 40 J
C 10 J
D 18 J

Answer:40 J
2 A block of wood is placed on a flat horizontal surface . A force F is applied to move it parallel to the surface . If I is the frictional force developed then the resultant face acting on the body , when it is sliding is
A F + f
B F - f
C Ff
D F / f

Answer:F - f
Advertisement
Article and Schedule Quiz Start Test!

DOWNLOAD CURRENT AFFAIRS PDF FROM APP

3 A machine gun fires a bullet of mass 40 g with a velocity of 1200 ms-1 . The man holding it can exert a maximum force on 144 N on the gum . How many bullets can he fire per second at the most ?
A one
B four
C two
D three

Answer:three
4 A passenger in a moving bus is thrown forward when the bus is suddenly stopped . This is explained
A by Newtons first law
B by Newtons second law
C by Newtons third law
D by the principle of conservation of momentum

Answer:by Newtons first law
5 A body of mass 10 kg is acted upon by two perpendicular forces, 6N and 8N. The resultant acceleration of the body is
A 1 m s–2 at an angle of tan-1 (4 / 3) w.r.t. 6N force.
B 0.2 m s–2 at an angle of tan-1 (4 / 3) w.r.t. 6N force.
C 1 m s–2 at an angle of tan-1 (3 / 4) w.r.t. 8N force.
D 0.2 m s–2 at an angle of tan-1 (3 / 4) w.r.t. 8N force.

Answer:A, c
6 Inside the nucleus , two protons are held together by a force which overcomes the repulsion . This force is called
A gravitationl force
B electrostatic force
C weak force
D strong force

Answer:strong force
7 The force required to produce an acceleration of 2 m/s2 on a mass of 2 kg is
A 4 N
B 10 N
C 22 N
D 18 N

Answer:4 N
8 Out of the basic forces , gravitational force
A ranks first in strength
B ranks second in strength
C ranks thrid in strength
D ranks fourth in strength

Answer:ranks fourth in strength
9 A heavy uniform chain lies on horizontal table top . If the coefficient of friction between the chain and the table surface is 0.25 , then the maximum fraction of the length of the chain that can hang over the edge of the table is
A 20%
B 25%
C 30%
D 35%

Answer:20%
10 The coefficient of kinetic friction is
A equal to the coefficient of static friction(t - 1.5t2)
B larger than the coefficient of static friction
C less than the coefficient of static friction
D independent of the value of the coefficient of static friction

Answer:less than the coefficient of static friction
11 A spring balance is attached to the ceiling of a lift . A msn hangs his bag on the spring and the spring reads 49 N, when the lift is stationary . If the lift moves downwards with an acceleration of 5 m/s , the reding of the spring balance will be
A 15 N
B 24 N
C 49 N
D 74 N

Answer:24 N
12 A block of wood is placed on a surface . A force is applied parallel to the surface to move the body . The frictional force developed acts
A normal to the surface upwards
B normal to the surface downwards
C along the direction of the applied force
D opposite to the direction of the applied force

Answer:opposite to the direction of the applied force
13 A passenger sitting in a bus moving at uniform speed, feels pushed backward whenever the bus is accelerated forward . This type of force is called
A Gravitational force
B real force
C fictitious force or pseudo force
D frictional force

Answer:fictitious force or pseudo force
14 The mass of a body is 2 kg . It weight is
A 19 .6 N
B 20 N
C 30 N
D 40 N

Answer:19 .6 N
15 The frame of reference attached to a satellite of the earth is
A an inertial frame
B an absolute frame at rest with respect to the stars
C a non - inertial frame
D a gravitational frame

Answer:a non - inertial frame
16 Two bodies of masses 4 kg and 5 kg are acted upon by the same force . If the acceleration of lighter body is 2 m/s2 , the acceleration of heavier body is
A 1 m/s2
B 1 . 2 m/s2
C 1 . 6 m/s2
D 1 . 8 m/s2

Answer:1 . 6 m/s2
17 A body of mass 5 kg is travelling with a uniform velocity of 2 m/s . Its momentum is
A 10 kg m/s
B 7 kg m/s
C 2 .5 kg m/s
D 3 kg m/s

Answer:10 kg m/s
18 Three forces acting at a point keep it in equilibrium . If the angle between two of the forces , 3 N and 3 N is 120o , then the third force is
A 3 N
B 5 N
C 1 N
D 12 N

Answer:3 N
19 Two forces 6 N and 8 N act at a point O . If the angle between the lines of action of the force is 90o , then their resultant is
A 14 N
B 12 N
C 10 N
D 48 N

Answer:10 N
20 A force of 12 N acts on a body of mass 2 kg . The acceleration produced on the body is
A 24 m/s2
B 6 m/s2
C 14 m/s2
D 10 m/s2

Answer:6 m/s2

ADRE 2.0 FULL LENGTH MOCK TEST

Take Mock Tests

Missiles Mock Test Start Test!
SSC MTS Mock Test Start Test
IBPS CLERK MOCK TEST Start Test
SSC MTS 2022 JULY 26 Shift 1 (ENGLISH) Start Test!
SSC GD Previous Year Paper 2021 Nov 17 Shift - I (Hindi) Start Test!
SSC CGL Tier - 1 PYP 2022 April 21 Shift- 1 (ENGLISH) Start Test!
MPSC PAPER I MOCK TEST 1 (ENGLISH) Start Test!
IB Security Assistant Mock test 1 (english) Start Test!
UP POLICE CONSTABLE MOCK TEST 1 Start Test!
DELHI POLICE CONSTABLE MOCK TEST 1 (HINDI) Start Test!

Chapters

Advertisement