Physics
Write true or false for each statement:
(a) Two trains going in opposite directions with the same speed are at rest relative to each other.
(b) A ball is thrown vertically upwards. Its motion is uniform throughout.
(c) The motion of a train starting from one station and reaching at another station is non-uniform.
(d) A motion which repeats itself after a fixed interval of time is called periodic motion.
(e) A ball thrown by a boy from a roof-top has oscillatory motion.
(f) Mass has both magnitude and direction.
(g) Weight always acts vertically downwards.
(h) Mass varies from place to place but weight does not.
Answer
(a) False
Correct Statement — Two trains going in opposite directions with the same speed are at motion relative to each other.
(b) False
Correct Statement — A ball is thrown vertically upwards. Its motion is non-uniform throughout.
(c) True
(d) True
(e) False
Correct Statement — A ball thrown by a boy from a roof-top has curvilinear motion.
(f) False
Correct Statement — Mass has only magnitude.
(g) True
(h) False
Correct Statement — Weight varies from place to place but mass does not.
Related Questions
Assertion (A): If a moving body travels equal distances in equal intervals of time, its motion is said to be uniform.
Reason (R): For uniform motion, the speed of the moving body remains constant.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true and R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Fill in the blanks:
(a) Two boys cycling on the road with the same speed are …………… relative to each other.
(b) The motion in a …………… is rectilinear motion.
(c) One to and fro motion of a clock pendulum takes time = …………… .
(d) 36 km h-1 = …………… m s-1.
(e) Total distance travelled = …………… x total time taken.
(f) The weight of a girl is 36 kgf. Her mass will be …………… .
(g) The weight of a body is measured using …………… .
Match the following:
Column A Column B (a) circular motion (i) a running fan (b) periodic motion (ii) a car moving in a market (c) vibratory motion (iii) movement of the hands of a clock (d) rotatory motion (iv) motion of wire of a guitar (e) non-uniform motion (v) motion of pendulum of a clock Comment on the statement 'rest and motion are relative terms'. Give an example.