Engineering Mechanics  GATE practice papers  Mechanical
Here, you can read Engineering Mechanics multiple choice questions and answers with explanation.
1) Two velocities are moving in such direction that the angle between them is 30°. The two velocities are having magnitudes 15 m/s and 25 m/s respectively. Calculate the magnitude of resultant velocity. (Marks: 02)  Published on 19 Oct 15
a. 30.47 m/s
b. 35 m/s
c. 38.72 m/s
d. none of the above
Answer
Explanation

ANSWER: 38.72 m/s
Explanation: By using parallelogram law,
w^{2 }=u^{2 }+ v^{2 }+ 2uv cos(a)
Where, w = magnitude of resultant velocity u = magnitude of first velocity v = magnitude of second velocity a = angle between first and second velocity


2) An object of 1 kg is attached to the string at the height of 100 m from the ground. What is the velocity of the object when it impacts on the ground, if it is released from string at 100 m? Take acceleration due to gravity g=9.8 m/s^{2} (Marks: 02)  Published on 19 Oct 15
a. 1960 m/s
b. 221.36 m/s
c. 44.27 m/s
d. none of the above
Answer
Explanation

ANSWER: 44.27 m/s
Explanation: No other than gravitational force is acting upon the object. Thus by using motion equation v^{2} = u^{2}+ 2as and taking initial velocity of the object u = 0, we can get the final velocity that is 44.27 m/s.

