Question

A particle in one dimensione
motion
a with zero speed at an instant
may have non-
zero acceleration at
that instant
b) with zero speed may
have non-zero velocity
c)with constant speeds must have
acceleration
d) with positive value of accelaration
must be speeding up
​

Answer 1

Answer:

A particle in one-dimensional motion: (a) with zero speed at an instant may have non-zero acceleration at the instant, (b) with zero speed may have non-zero velocity, (c) with constant speed must have zero acceleration, (d) with positive value of acceleration must be speeding up. Answer: (a) True.

Answer 2

Answer:

a- true

b- false

c-false

d- false

Explanation:

a- this is possible. Let us take an example......when you throw an object in the upward direction, at the maximum height, its speed is zero, but its acceleration is 9.8 m per second square.

b- Speed can be written as distance by time and velocity can be written as displacement by time......Distance is always greater than or equal to displacement...so if speed is zero, then velocity is also zero, it cant be more than speed.

c- a body with a constant speed may have acceleration.......for example, a body in a circular motion. But this is not always the case. Therefore, a particle doesn't have to have acceleration at a constant speed.

d- When a particle has positive acceleration, it doesn't have to be speeding up....just like in the previous example, whea body is in circular motion.