Work and Energy MCQs
Multiple choice questions.
1.) The work done W by the force F as the scalar product of ‘F’ and ‘d’ displacement then W = F.d______
a)sinθ.
b) cosθ
c) tanθ.
d) sin²θ
Ans : b) cosθ
2.) The work done W by the force F as the scalar product of ‘F’ and ‘d’ displacement,If θ<90°, work done is said to be
a) Positive work b) Nagetive work
c) No work done. d) equal work
Ans : a) Positive work
3.) The work done W by the force F as the scalar product of ‘F’ and ‘d’ displacement, If θ = 90° work done is said to be
a) Positive work
b) Nagetive work
c) No work done.
d) equal work
Ans : c) No work done
4). The work done W by the force F as the scalar product of ‘F’ and ‘d’ displacement,If θ >90° , work done is said to be
a) Positive work
b) Nagetive work
c) No work done.
d) equal work
Ans : b) Nagetive work
5.) Fill in the blank.
The work done on a body by a _______ force is defined as the product of the magnetudes of the displacement and the component of the force in the direction of the displacement.
a) constant. b) zero
c) one. d) nagetive
Ans : a) constant
6.) The space arround the Earth in which its gravitational force acts on a body is called
a) Gravitational Velocity
b) Gravitational acceleration
c) Gravitational field
d) Gravitational displacement
Ans : c) Gravitational field
7.) If displacement is in the direction of gravitational force, then work done is
a) Positive. b) Nagetive
c) Constant. d) Zero
Ans : a) Positive
8.) If displacement is against the gravitational force, then work done is
a) Positive. b) Nagetive
c) Constant. d) Zero
Ans : b) Nagetive
9.) Fill in the blank.
Work done in the Earth’s gravitational field is __________ of the path followed.
a) dependent.
b) independent
c) distained.
d) positive
Ans : b) independent
10.) The field in which the work done be independent of the path followed or work done in a closed path be zero, is called.
a) Gravitational field.
b) Conservative field
c) Field density.
d) Field velocity
Ans : b) Conservative field
11.) The measure of the rate at which work is being done is called
a) Gravitational field.
b) Field density
c) Power.
d) Force
Ans : c) Power
12.) The average power can be defined as, Pav = _________
a)∆W/∆t.
b)∆W/t
c) W/∆t.
d) W/t
Ans : a) ∆W/∆t
13.) The relation between power and constant velocity can be defined as, P =_____
a)F/v.
b)F.v
c) ∆F/v.
d) ∆F/∆v
Ans : b) F.v
14.) One Joule of work done in one second can be written as,
a) Pascal.
b) Watt
c) Coulomb.
d) Newton
Ans : b) Watt
15.) 1 kilowatthour can be written as
a) 1.6KJ.
b) 3.6MJ
c) 2.8 PW.
d) 4.2 Ms
Ans : b) 3.6MJ
16.) The capacity to do work is called
a) Force.
b) Energy
c) Gravity
d) Capacitance
Ans : b) Energy
17.) Kinetic energy can be defined as
a)2mv².
b) ½mv²
c) mgh.
d) ½mgh
Ans : b) ½mv²
18.) Potential energy can be defined as
a) 2mv².
b) ½mv²
c) mgh.
d) ½mgh
Ans : c) mgh
19.) Work done on the body is _______ to the change in its kinetic energy.
a) equals.
b) ½ times equals
c) ⅓ times equals.
d) ¼ times equals
Ans : a) equals
20.) Absolute potential energy, Ug can be defined as
a)GMm/R.
b) -GMm/R
c) -GM/Rm.
d) Mm/GR
Ans : b) -GMm/R
21.) Escape velocity can be defined as vesc = ______
a)√2×gR.
b) √(2g) ×R
c) √(2gR).
d) gR /√2
Ans : c) √(2gR)
22.) The approximate value of escape velocity of Earth’s surface is
a)9.8 ms-1
b) 10.2 kms-1
c) 11 kms-1.
d) 1.6 ms-1
Ans : c) 11 kms-1
23.) Loss in potential energy = ________+ Work done against friction
a) Gain in potential energy
b) Gain in kinetic energy
c) Loss in potential energy
d) Loss in work done
Ans : b) Gain in kinetic energy
24.) Complete the formula of loss of potential energy, mgh = ½mv² + _______
a) fh.
b) ∆t/f
c) ∆d/∆h.
d) f/∆t
Ans : a) fh
25.) Energy cannot be destroyed. It can be transformed from one kind into another, but the total amount of energy remains _________
a) vanishes. b) constant
c) destroyed. d) Nagetive
Ans : b) constant
26.) The potential energy is possessed by a body because of its position in a _______
a) gravitational field. b) force field
c) electric field. d) velocity field
Ans : b) force field
27.) The initial velocity of a body with which it should be projected upward so that it does not come back, is called
a) Gravitational velocity
b) Escape velocity
c) Field velocity
d) Translation velocity
Ans : b) Escape velocity
28.) Escape velocity can be defined as, v = ________
a)√2×(GMR).
b)(√(2GM))/R
c) √(2GM/R).
d)√(2GMR)
Ans : c) √(2GM/R)