m = mass of pellet = 2.10 x 10⁻² kg
x = compression of spring at the time launch = 9.10 x 10⁻² m
h = height gained by the pellet above the initial position = 6.10 m
k = spring constant
using conservation of energy
spring potential energy = gravitational potential energy of pellet
(0.5) k x² = m g h
inserting the values
(0.5) k (9.10 x 10⁻²)² = (2.10 x 10⁻²) (9.8) (6.10)
k = 303.2 N/m
The average velocity of Sandy is given by the total distance covered S divided by the total time taken t:

The total distance covered is

while the total time taken is 2 hours + half an hour (for the rest) + 1 hour and half, so

Therefore, the average velocity is
Answer:
KE_2 = 3.48J
Explanation:
Conservation of Energy
E_1 = E_2
PE_1+KE_1 = PE_2+KE_2
m*g*h+(1/2)m*v² = m*g*h+(1/2)m*v²
(0.0780kg)*(9.81m/s²)*(5.36m)+(.5)*(0.0780kg)*(4.84m/s)² = (0.0780kg)*(9.81m/s²)*(2m)+KE_2
4.10J+0.914J = 1.53J + KE_2
5.01J = 1.53J + KE_2
KE_2 = 3.48J
Answer:Although any object in motion through space (for example a thrown baseball, kicked football, fired bullet, thrown arrow, stone released from catapult) are projectiles, they are commonly found in warfare and sports.
Explanation: