## Physics Quiz 4, Question from Laws of Motion.

1. If the lift in problem, moves up with an acceleration equal to the acceleration due to gravity, the reading on the spring balance will be ?

2. A man is standing on a weighing machine placed in a lift, when stationary, his weight is recorded as 40 kg. If the lift is accelerated upwards with an acceleration of 2m /s 2 , then the weight recorded in the machine will be (g = 10 m/s 2) ?

3. An elevator weighing 6000 kg is pulled upward by a cable with an acceleration of 5 ms -2 . Taking g to be 10 ms -2 , then the tension in the cable is ?

4. The ratio of the weight of a man in a stationary lift and when it is moving downward with uniform acceleration ‘a’ is 3 : 2. The value of ‘a’ is (g- Acceleration due to gravity on the earth) ?

5. A 60 kg man stands on a spring scale in the lift. At some instant he finds, scale reading has changed from 60 kg to 50 kg for a while and then comes back to the original mark. What should we conclude ?

6. A bird is sitting in a large closed cage which is placed on a spring balance. It records a weight placed on a spring balance. It records a weight of 25 N. The bird (mass = 0.5kg) flies upward in the cage with an acceleration of 2m /s 2 . The spring balance will now record a weight of ?

7. A bird is sitting in a wire cage hanging from the spring balance. Let the reading of the spring balance be W 1 . If the bird flies about inside the cage, the reading of the spring balance is W 2 . Which of the following is true ?

8. Two blocks of mass 4 kg and 6 kg are placed in contact with each other on a frictionless horizontal surface. If we apply a push of 5 N on the heavier mass, the force on the lighter mass will be ?

9. In the above problem, if a push of 5 N is applied on the lighter mass, the force exerted by the lighter mass on the heavier mass will be ?