Question

Q1) Assertion : a vector can be resolved into maximum two components

Reason : in projectile motion the velocity is resolved into vertical and horizontal components

a) Both A and R are correct; R is the correct explanation of A
b) Both A and R are correct; R is not correct explanation of A
c) A is correct; R is not correct
d) A is not correct; R is correct

Q2) Assertion : speed is constant in uniform circular motion
Reason : acceleration is constant in uniform circular motion

a) Both A and R are correct; R is the correct explanation of A
b) Both A and R are correct; R is not correct explanation of A
c) A is correct; R is not correct
d) A is not correct; R is correct
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Answer 1

Step-by-step explanation:

Q1) d) A is not correct; R is correct (sort of) but is not the reason for A.

A vector may be resolved into an infinite number of components.

Breaking a projectile motion into the vertical and horizontal components is the EASIEST way to solve it because acceleration can be assumed to be constant in both directions. Zero for horizontal and g(ravity) in the vertical. However it is not the ONLY way to do it. Other ways are much more complex.

Q2) a) Both A and R are correct; R is the correct explanation of A (sort of)

A is correct. Speed is constant in uniform circular motion.

R is correct if you call CENTRIPETAL acceleration constant. It is only constant in magnitude. The direction is always changing as the vector always points toward the center of rotation.