Question

what is the vertical motion of the ball thrown in the air with an initial velocity of 12 m/s at an angle of 30 degree? a. 5 m/s b. 6 m/s c. 6.93 m/s d. 10.39 m/s

Answer 1

Given

A ball is thrown in the air with an initial velocity of 12 m/s at an angle of 30°

To Find

Vertical velocity of the ball

Solution

We know that

$\rm \longrightarrow u_{y}=u \times \sin (\theta)$

Here

• $\rm u_{y}$ = vertical velocity
• $\rm u$ = initial velocity
• $\rm \theta$ = angle of projection

Units

• $\rm u_{y}$ = metres per second (m/s)
• $\rm u$ = metres per second (m/s)
• $\rm \theta$ = degree (°)

According to the question

We are asked to find the vertical velocity of the ball

Therefore

We must find " $\rm u_{y}$ "

Given that

A ball is thrown in the air with an initial velocity of 12 m/s at an angle of 30°

Hence

• u = 12 m/s
• θ = 30°

Substituting the values

We get

$\rm \longrightarrow u_{y}=12 \times \sin (30^{\circ}) \ m/s$

We know that

$\sf \implies\sin (30^{\circ})=\dfrac{1}{2}$

So

$\rm \longrightarrow u_{y}=12 \times \dfrac{1}{2} \ m/s$

$\rm \longrightarrow u_{y}= \dfrac{12}{2} \ m/s$

Hence

$\rm \longrightarrow u_{y}=6 \ m/s$

So

Vertical velocity of the ball = 6 m/s

Therefore

Option (b) is correct