Chapter 7
Work, Energy, and Simple Machines
CBSE Class 9
Science Solutions
Educart Science class Class 9 NCERT Exemplar cover
Question:

When a ball thrown upwards reaches its highest point, which of the following statement(s) are correct?

(a) The force acting on the ball is zero.

(b) The acceleration of the ball is zero.

(c) Its kinetic energy is zero.

(d) Its potential energy is maximum.

Answer: Verified

(c) and (d)

Explanation: At the highest point, the velocity of the ball becomes zero, so its kinetic energy is zero. Since the ball is at the maximum height, its potential energy is maximum. Gravity still acts on the ball, so force and acceleration are not zero.

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More NCERT Questions
Explain why roads on hills are built to wind around in gentle slopes rather than going straight up? [Pg. No. 132] Why is it easier to open the lid of a can by using a spoon as shown in Figure.[Pg. No. 135] To reach a higher floor, we find climbing an inclined ladder easier in comparison to climbing a vertical ladder. Explain why.[Pg. No. 132] State whether True or False. (A) Work is said to be done when a force is applied, even if the object does not move. (B) Lifting a bucket vertically upward results in positive work done on the bucket.