Two children of different masses are sitting on identical swings. Class 9

Two children of different masses are sitting on identical swings. Class 9

Question 1.

Two children of different masses are sitting on identical swings. To impart identical initial acceleration, for which child would you require to apply a larger force? Explain why. Class 9

Answer:

You would require a larger force for the heavier child. By Newton's second law: F = ma. For the same acceleration (a) to be imparted, the force (F) must be proportional to the mass (m). The heavier child has a larger mass, so a larger force must be applied to produce the same acceleration.

Question 2.

How are glass items packed for transportation using a bubble wrap or hay protected from damage? Class 9

Answer:

When glass items experience a jolt during transportation, they are in contact with bubble wrap or hay. When a force is applied on the glass item (e.g., due to vibration or a knock), the soft material increases the time over which the velocity of the item changes. By Newton's second law, a longer time for the same change in velocity means a smaller acceleration, and therefore a smaller force on the glass. This smaller force is less likely to break the fragile item.