Question

2. An object start from the rest With acceleration of 8m/s² along straight.find
A .the speed at the end of 5 sec.
B.the average speed for 5 sec interval
C .the distance traveled in 5 sec.

Answer 1

To solve these problems, we can use the kinematic equations of motion. In this case, we need to use the equation:

v = u + at,

where:
v = final velocity (speed),
u = initial velocity (speed),
a = acceleration, and
t = time.

Given:
u = 0 m/s (the object starts from rest),
a = 8 m/s² (acceleration),
t = 5 sec (time).

A. The speed at the end of 5 seconds can be found using the equation:

v = u + at.

Substituting the given values:

v = 0 + (8)(5).
v = 0 + 40.
v = 40 m/s.

Therefore, the speed at the end of 5 seconds is 40 m/s.

B. The average speed for a 5-second interval can be found using the equation:

average speed = total distance / total time.

Since the object is accelerating uniformly, the average speed is the same as the final speed. Therefore, the average speed for a 5-second interval is also 40 m/s.

C. The distance traveled in 5 seconds can be found using the equation:

distance = initial velocity × time + (1/2) × acceleration × time².

Since the initial velocity is 0 m/s:

distance = 0 × 5 + (1/2) × 8 × 5².
distance = 0 + (1/2) × 8 × 25.
distance = 0 + 100.
distance = 100 meters.

Therefore, the distance traveled in 5 seconds is 100 meters.