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

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.

(C) The SI unit for both work and energy is joule (J).

(D) A motionless stretched rubber band has kinetic energy.

(E) Energy can change from one form to another.

Answer: Verified

(A) False

Explanation: Work is done only when force causes displacement.

(B) True

Explanation: Force and displacement are in the same upward direction.

(C) True

(D) False

Explanation: A stretched rubber band has potential energy, not kinetic energy.

(E) True

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