Question

PLEASE ANSWER THESE FAST

1. A stone is thrown vertically down at 30 m/s from the top of a 50 m high building. Simultaneously
another stone was thrown vertically up at 20 m/s from the bottom of the building in the same line as
that of first stone. After what time will the two stone hit.
(a) 1 s (b) 2 s (c) 5 s (d) 4 s
2. A boy standing between two cliffs shouts “Hello” and hears two echoes after 1 sec and 2 sec. What is
the distance between the two cliffs. (Speed of sound = 340 m/s)
(a) 680 m (b) 1020 m (c) 510 m (d) 340 m
3. A block kept on a frictionless inclined plane is released so that it slides down. Find the speed with
which it reaches at the bottom.
(a) 20 m/s (b) 4m/s (c) 10 m/s (d) 5 m/s
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4. Value of acceleration due to gravity on moon's surface is 1.6 ms
-2
. A body which weighs 180 N on
earth's surface will weigh how much on moon’s surface.
(a)112.5 N (b) 30 N (c) 120 N (d) 60 N
5. If no net force is applied on a body, then it is said to be in
(a) distance (b) Motion (c) linear motion (d) equilibrium
6. A stone is fired with the speed of 20 m/s at an angle of 45 degrees from ground. Calculate the
displacement of the particle along the horizontal.
(a) 30 m (b) 40 m (c) 50 m (d) 60 m
7. A ball is floating with ⅓ rd of its volume inside the water. What is the ratio of density of water to
the density of ball.
(a) 3 (b) ⅓ (c) 30 (d) 1/30
8. Sound of high pitch has
(a) High Frequency (b) High Amplitude (c) Low Frequency (d) Low
Amplitude
9. Gravitational Potential Energy of a body changes with
(a) Horizontal Displacement (b) Horizontal Distance ( c) Slant height (d)Height
10. Total work done on a body is equal to change in its
(a) Potential Energy (b) Kinetic Energy (c) Mechanical Energy (d) Temperature

Answer 1

Answer:

1 .. C

2.. D

3.. Question not correct

4.. B

5.. C

6.. B

7... A

8.. Both A & D

9 ... A

10.. B