Respuesta :
Answer:
The velocity with which the stone leaves the catapult is 4 m/s
Explanation:
The mass of the stone released, m = 50 g = 0.05 kg
The length by which the rubber catapult is stretched, Īx = 4 cm = 0.04 m
The force constant of the rubber, k = 500 N/m
By the conservation of energy formula, we have;
Kā + Uā = Kā + Uā
Where;
Kā = The initial kinetic energy of the stone and the catapult system = 0 J (The stone Ā and the rubber of the catapult are held back stationary)
Uā = The initial potential energy of the stone and the catapult system = 1/2Ā·kĀ·(Īx)²
Kā = The final kinetic energy of the stone and the catapult system = 1/2Ā·mĀ·v²
Where;
v = The velocity with which the stone leaves the catapult
Uā = The final potential energy of the stone and the catapult system = 0 J (The rubber of the catapult returns to the relaxed state)
Therefore, by substitution of the above values and equivalent expressions, we have;
0 J + 1/2Ā·kĀ·(Īx)² = 1/2Ā·mĀ·v² + 0 J
1/2Ā·kĀ·(Īx)² = 1/2Ā·mĀ·v²
We substitute the given known values as follows;
1/2 à 500 N/m à (0.04 m)² = 1/2 à 0.05 kg à v²
ⓠv² = (1/2 à 500 N/m à (0.04 m)²)/(1/2 à 0.05 kg) = 16 m²/s²
v = ā(16 m²/s²) = 4 m/s
The velocity with which the stone leaves the catapult = v = 4 m/s.