Multiple Choice QuestionsThe physical quantity having the dimensions [ M-1 L-3 T3 A2 ] is
resistance
resistivity
electrical conductivity
electromotive force
Velocity-time curve for a body projected vertically upwards is
parabola
ellipse
hyperbola
straight line
D.
straight line
When the ball goes upwards the direction of velocity of the ball and the direction of acceleration of gravity are in the opposite directions of acceleration of gravity are in the opposite directions so the velocity of the ball decrease until it reaches the top and stops momentarily.
v = u - gt ... (i)
Then from the peak position, the ball will start to descend downwards due to the acceleration due to gravity that is g.
v = -gt ....(ii)
( negative sign is due to motion in downward direction)
From both equations, the velocity and time are linearly proportional to each other which is the same as the equation of a straight line. So this graph will be a straight line starting from initial velocity (u) on the y-axis and slope g with time as the x-axis.
The numerical ratio of displacement to the distance covered is always
less than one
equal to one
equal to or less than one
equal to or greater than one
A train is moving towards east and a car is along north, both with same speed. The observed direction of car to the passenger in the train is
east-north direction
west-north direction
south-east direction
None of the above
A solid sphere and a hollow sphere of the same material and of a same size can be distinguished without weighing
by determining their moments of inertia about their coaxial axe
by rolling them simultaneously on an inclined plane
by rotating them about a common axis of rotation
by applying equal torque on them
Point masses 1, 2, 3 and 4 kg are lying at the points (0, 0, 0), (2, 0, 0), (0, 3, 0) and (- 2, -2, 0) respectively. The moment-of inertia of this system about X-axis will be
43 kg-m2
34 kg-m2
27 kg-m2
72 kg-m2
The radius of gyration of a body about an axis at a distance 6 cm from its centre of mass is 10 cm. Then, its radius of gyration about a parallel axis through its centre of mass will be
80 cm
8 cm
0.8 cm
80 m
A bullet of mass 20 g and moving with 600 m/s collides with a block of mass 4 kg hanging with the string. What is velocity of bullet when it comes out of block, if block rises to height 0.2 m after collision?
200 m/s
150 m/s
400 m/s
300 m/s
Voltage in the secondary coil of a transformer does not depend upon
frequency of the source
voltage in the primary coil
ratio of number of turns in the two coils
Both (b) and (c)
A ball of mass 2 kg moving with velocity 3 m/s collides with spring of natural length 2 m and force constant 144 N/m. What will be length of compressed spring?
2 m
1.5 m
1 m
0.5 m
Switch
