Question

The x-t graph and the v-t graph of a ball thrown up will a speed of 10 m/s at t = 0 till it comes back.

• A.
• B.
• C.

Answer 1

The correct option is A

$v^2=u^2+as$

When v = 0, it is at is highest point

$\therefore 0={10}^2+2(-10)s$

0 = 100 - 20s

$\Rightarrow$20s = 100

$\Rightarrow$s = 5m

v = u + at

$\Rightarrow$0 = 10 + (- 10) (t)

$\Rightarrow$0 = 10 - 10t

$\Rightarrow$10 = 10t

$\Rightarrow$t = 1

$\therefore$ It takes 1 sec to reach v = 0. x - t will be a downward curving parabola as $v=\frac{dx}{dt}$ (slope of x-t graph) is reducing constantly.