Basic force MCQs
The physical quantity can changes the state of a object from rest to motion or vice versa is called as Force. The whole universe is balanced by four basic forces known as fundamental forces viz;
1. Gravitational force: The force by which the object gets attracted towards the centre of Earth is known as gravitational force. Sir Isaac Newton has studied this force and explained the formula for it by his famous and universal law of gravitation. According to him, “Every object in universe attracts every other object with the force which is directly proportional to product of the masses and inversely proportional to square of the distance between the objects”.
Here G is constant known as Universal gravitational constant. The value of G were found by Cavendish which is G=6.67×10-11 N-m2/kg2.
2. Electrostatic force: The force exerted by charges at rest is known as electrostatic force. This force may be attractive or repulsive. The like charges repels, whereas unlike charges attracts. The formula for this force were given by Coulomb’s law, which is,
Where q1 and q2 are charges and r is distance between charges.
3. Strong Nuclear force: The force which holds the nuclei together is known as Strong Nuclear force. This is shortest range force hence it is strongest force.
4. Weak nuclear force: The force between nuclei like Uranium, Thorium is known as weak nuclear force. This is weaker force because of which the nuclei undergo decay process. The materials which undergo decay are known as radioactive elements, and the process is known as radioactivity.
Q.1) The gravitational force were discovered by…
a) Galileo
b) Kepler
c) Newton
d) Cavendish
Q.2) The magnitude of gravitational force at the centre of earth is…..
a) Maximum
b) Minimun
c) Zero
d) Cannot be predicted
Q.3) Which among the following is the weakest force?
a) Gravitational force
b) Electrostatic force
c) Electromagnetic force
d) Nuclear force
Q.4) The force due to which negatively charged electron revolves around the positively charged nucleus is…
a) Gravitational force
b) Nuclear force
c) Atomic force
d) Electrostatic force.
Q.5) The strongest force among the following is….
a) Gravitational force
b) Electrostatic force
c) Electromagnetic force
d) Nuclear force
Q.6) SI unit of permittivity of free space is….
a) C2 /N.m2
b) N2 /C.m2
c) C2 /N2.m
d)N2 /C
Q.7) The magnitude of Universal gravitational constant in CGS unit is…..
a) 67×10-11 dyne-cm2/g2
b) 67×10-8dyne-cm2/g2
c) 67×10-5dyne-cm2/g2
d) 67×10-13dyne-cm2/g2
Q.8) Range of nuclear forces is…….
a) < 10-14 m
b)> 10-14 m
c)< 10-10 m
d) > 10-10 m
Q.9) Range of weak nuclear force is……
a) of order of 10-12 m
b) of order of 10-14 m
c) of order of 10-16 m
d) of order of 10-18 m
Q.10) The process of radioactive beta decay is usually takes place due to…
a) Gravitational force.
b) Strong Nuclear force.
c) Atomic force.
d) Weak Nuclear force.
Answers:
Q.1) c) Newton
Q.2) c) Zero
Q.3) a) Gravitational force
Q.4) d) Electrostatic force
Q.5) d) Nuclear force
Q.6) a) C2 /N.m2
Q.7) b) 6.67×10-8dyne-cm2/g2
Q.8) a) < 10-14 m
Q.9) c) of order of 10-16 m
Q.10) d) Weak Nuclear force.