Uniform and Non Uniform Motion

Q.

It was a rainy day in Bangalore. Rohit was sitting besides the window when he saw a lightning. He started his stop watch. He found that after $22$ seconds of lightning its roaring was heard. Calculate the height of the clouds which caused this lightning. Given, speed of light = $3\times {10}^8$ $m{s}^{-1}$ and speed of sound = $340m{s}^{-1}$.

1. $8.5km$
2. $7.5km$
3. $5km$
4. $10km$

Q. A body is said to be in uniform motion, if it covers unequal distance in equal interval of time.

1. True
2. False

Q. If an object moves with constant speed, then the motion of the object is said to be uniform.

1. False
2. True

Q.

If a body is moving in a straight line but it keeps changing its speed, then the motion of the body is _____.

1. non-uniform

2. uniform

3. periodic

4. circular

Q.

A body moving in the same direction is said to be in uniform motion if:

1. it covers equal distance in equal intervals of time

2. it covers unequal distance in equal intervals of time

3. it covers equal distance in unequal intervals of time

4. it covers unequal distance in unequal intervals of time

Q. The least number which is exactly divisible by 20, 30 and 40 is ____.

1. 100
2. 120
3. 180
4. 150

Q. Find the LCM of 9, 12 and 15.

1. 140
2. 160
3. 200
4. 180

Q. Find the LCM of first 5 multiples of 4.

1. 520
2. 220
3. 480
4. 100

Q. The least common multiple of 9, 18, 57 and 12 is _____.

1. 228
2. 684
3. 36
4. 114

Q. Three measuring rods are 6 cm, 4 cm and 8 cm long. Find the shortest length that can be measured exactly by each one of these rods.

1. 48 cm
2. 32 cm
3. 24 cm
4. 40 cm