Applied Mechanics 3

Objective Questions and Answers of Civil Engineering: Applied Mechanics 3

Subject: Applied Mechanics 3

Part 3: Objective questions and answers of Applied Mechanics

Q1. For a given velocity of a projectile, the range is maximum when the angle of projection is

a) 30°

b) 45°

c) 90°

d) 0°

Q2. If a projectile is fired with an initial velocity of 10 m/sec at an angle of 60° to the horizontal, its horizontal and vertical velocity at the highest point of trajectory are

a) 0 and 5 m/sec

b) 5 m/sec and 0

c) 5 v^3 m/sec and 0

d) 5 and 5v^3 m/sec

Q3. Rate of change of angular momentum is equal to

a) Force

b) Torque

c) Linear momentum

d) Impulse

Q4. A flywheel of moment of inertia 20 kg-m” is acted upon by a tangential force of 5 n at 2 m from its axis, for 3 seconds. The increase in angular velocity in radian per second is

a) 1/2

b) 3/2 ‘

c) 2

d) 3

Q5. At the instantaneous center, the velocity of the moving lamina at any instant is

a) Zero

b) Maximum

c) Minimum

d) Varying

Q6. The maximum value of the horizontal range for a projectile projected with a velocity of 98 m/sec is

a) 98 m

b) 490 m

c) 980 m

d) 1960 m

Q7. A projectile has maximum range of 40 m on a horizontal plane. If angle of projection is a and the time of flight is 1 second, then sin a must be about

a) 1/4

b) 1/3

c) 1/2

d) 1/5

Assume g = 10 m/sec^2

Q8. In a simple harmonic motion, the position of equilibrium is always

a) Stable

b) Unstable

c) Neutral

d) None of the above

Q9. A simple pendulum of length 1 has an energy e when its amplitude is a. If its amplitude is increased to 2 a, the energy becomes

a) E

b) E/2

c) 2e

d) 4e

Q10. A particle is executing simple harmonic motion in a line 1.0 m long. If the time of one complete vibration is 1 sec, then the maximum velocity of the particle is

a) 1.00 m/sec

b) 1.57 m/sec

c) 3.14 m/sec

d) 6.28 m/sec

Q11. The maximum displacement of a particle executing s.h.m. corresponds to

a) Zero potential energy and maximum kinetic energy

b) Zero kinetic energy and maximum potential energy

c) Maximum kinetic energy and maxi-mum potential energy

d) Minimum kinetic energy and minimum potential energy

Q12. The ratio of kinetic energy and potential energy of a simple harmonic oscillator, at a displacement equal to half its amplitude is given by

a) 1:2

b) 1:1

c) 2:1

d) 3:1

Q13. The time period of a simple pendulum depends on

I) Mass of suspended particle

Ii) Length of the pendulum

Iii) Acceleration due to gravity the correct answer is

a) Only (i)

b) Both (ii) and (iii)

c) Both (i) and (iii)

d) All are correct

Q14. Joule is the unit of

a) Power

b) Impulse

c) Work

d) Momentum

Q15. The dimensions of gravitational universal constant ‘g’ are

a) M-‘l2r2

b) M-‘l3r2

c) M-2l3t2

d) M’l3t2

Q16. One joule is equivalent to

a) 9.81 newton – metre

b) 1 newton – metre

c) 1 kg wt – metre

d) 1 dyne – metre

Q17. A quantity measured in the c.g.s system of units has dimensions m”2l3 t3/2. What numerical factor would be required to convert the quantity to si units?

a) 1

b) 100

c) 1/100

d) 1/10000

Q18. The ratio of unit of force in gravitational system to that in absolute system is

a) 1

b) G

c) 1/g

d) None of the above

Where ‘g’ is acceleration due to gravity

Q19. The dimensions of power are.

a) M’l2t2

b) M’l’t3

c) M’l’r2

d) M’l-‘t*

Q20. One newton is equivalent to

a) 1 kg-wt

b) 9.81 kg-wt

c) 981 dyne

d) 1/9.81 kg-wt

Part 3: Objective questions and answers of Applied Mechanics