Question

An object is thrown vertically upwards to a height of 30 m. Calculate its a) Velocity with which it was thrown upwards.

Answer 1

Given:-

• Height ,h = 30 m

• Final velocity ,v = 0m/s

• Acceleration due to gravity ,g = 10m/s²

To Find:-

• Initial velocity ,u

Solution:-

Using 3rd Equation of Motion

❒ v² = u² +2gh

where

v is the final velocity

g is the acceleration

u is the initial velocity

h is the height

Substitute the value we get

→ 0² = u² + 2×(-10) × 30

→ 0 = u² + (-20)×30

→ -u² = -600

→ u² = 600

→ u =√600

→ u = 24.50 m/s

Therefore, the object was thrown upward as the speed of 24.50 m/s.

Answer 2

Answer:

Given :-

• An object is thrown vertically upwards to a height of 30 m.

To Find :-

• Velocity with which it was thrown upwards.

Formula Used :-

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

where,

• v = Final velocity
• u = Initial velocity
• g = Acceleration due to gravity
• h = Height

Solution :-

Given :

• v = 0 m/s
• g = 10 m/s²
• h = 30 m/s²

According to the question by using the formula we get,

⇒ (0)² = (u)² + 2(10)(30)

⇒ 0 = u² + 2(300)

⇒ u² = 600

⇒ u = $\sqrt{600}$

➠ u = 24.50 m/s

$\therefore$ The velocity with which it was thrown upwards is 24.50 m/s .