Question

CORRECT AND CLEAR ANSWER WILL BE GIVEN BRAINLIEST An object of mass 0.30 kg is thrown vertically upwards and reaches a height of 8.0 m. Calculate: (a) it's final potential energy (b) The velocity with which it must be thrown, neglecting air resistance ( assuming g = 10m/s²)

Answer 1

Answer:

Final potential energy = 24 Joule

The velocity with which object must be thrown = $4 \sqrt{10}$ m/s

Step-by-step explanation:

Given:

Mass of object, m = 0.30 Kg

Height of object, h = 8 m

Acceleration due to gravity, g = 10 $ms^{-2}$

a) Formula for Potential Energy:

$E_p =mgh$

Where m is the mass of object

g is acceleration due to gravity and

h is the height of object

Putting the values of m, g and h

$E_p = 0.3 \times 10 \times 8\\\Rightarrow E_p =24 J$

b) Formula for initial and final velocity:

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

where v is the final velocity

u is the initial velocity with which the object is thrown

g is acceleration due to gravity and

h is the height obtained by object

here v = 0 at the height 8 m because it will come to rest at the point it attains the maximum height.

h = 8m

g = -10 $ms^{-2}$ (negative because the object's velocity is decreasing)

Putting the values to find 'u':

$0^{2} =u^{2} +2 \times -10 \times 8\\\Rightarrow u^{2} = 160\\\Rightarrow u = 4 \sqrt{10}\ m/s$