# GATE 1998 Mechanical Questions with Answers

Hello Friends,
Preparing for GATE exams 2018 or TRP Govt Polytechnic Exams or IES examinations or any other Govt exams for Mechanical Engineering? Then this is the post where you can get previous years GATE exam questions which are solved. Here is a question paper from GATE 1998 year for Mechanical Engineering. You can refer the questions and answers provided here for your future exams.

1. A car moving with uniform acceleration covers 450 m in a 5 second interval, and covers 700 m in the next 5 second interval. The acceleration of the car is:
(a) 7 m/s^2
(b) 50 m/s^2
(c) 25 m/s^2
(d) 10 m/s^2
Explanation:
u = initial velocity
v = final velocity
a = acceleration
t = time
s = distance

using the relation s = ut + 1/2 at^2 and v=u + at, for the first 5 second interval, we have,
450 = 5u + 25/2 a  ...... (i)
v = u + 5a

For the next 5 second interval (v=u + 5a) will be the initial velocity, then
700 = (u + 5a) 5 + 25/2 a
700 = 5u + 25a + 25/2 a  ..... (ii)

From equations (i) and (ii), we get
700-450 = (5u +25a + 25/2 a) – (5u + 25/2 a)
250 = 25a
a = 250/25
a =10 m/s^2

2. The buckling load for a column pinned at both ends is 10 kN. If the ends are fixed, the buckling load changes to
(a) 40 kN (b) 2.5 kN (c) 5 kN (d) 20 k N

3. The normal stresses at a point are σ x = 10 MPa and, 2 MPa; σ y = the shear stress at this point is 4 MPa. The maximum principal stress at this point is:
(a) 16 MPa (b) 14 MPa (c) 11 MPa (d) 10 MPa
Explanation: Using the formula given below, find out σmax which is the maximum principal stress.

4. The ratio of average shear stress to the maximum shear stress in a beam with a square cross-section is:
(a) 1 (b) 2/3  (c) 3/2 (d) 2