Question

plz solve its urgent

Answer 1

Hello friend,

1. Since the car starts from rest, u = 0 m/s
In time, t = 5 sec,
The car gains the velocity, v = 5 m/s
As we know,
Acceleration, a = (v - u) ÷ t = (5 - 0) ÷ 5 = 5 ÷ 5 = 1 m/s^2

Hence your answer i.e. Acceleration = 1 m/s^2

2. As the ball is thrown with an inital velocity, v = 5 m/s

Anything when thrown from earth's surface reaches a maximum height and at that height, it's final velocity always becomes zero.
So,
Here, v = 0 m/s
Given,
It reaches maximum height in time, t = 6 sec
Also, Earth attracts every body with a force and produces acceleration or retardation in it. This acceleration is called acceleration due to gravity and is denoted by ' g '.
Although the value of ' g ' changes with place but unless mentioned in the question it is taken 9.8 m/s^2
So here, g = 9.8 m/s^2

Recal Newton's third law of inertia!
According to this law,
${v}^{2} = {u}^{2} + 2as$
Here 's' can be taken 'h' and 'a' can be taken as 'g'


${v}^{2} = {u}^{2} + 2gh \\ \:$

Substituting the values,
(0)^2 = (5)^2 + 2 * 9.8 * h
0 = 25 + 19.6h
19.6h = 25
$h = \frac{25}{19.6} \\ h = \frac{25}{196} \times 10 \\ h = \frac{250}{196} = 1.27 \: m$

Hope it helps!