Answer:
3.196 m/s
Explanation:
Parameters given:
Mass of Brittany and the skateboard, M = 62 kg
Mass of pumpkin, m = 3.7 kg
Initial speed of Brittany and the skateboard, U = 0 m/s
Final velocity of Brittany, the skateboard and the pumpkin, V = v = 0.18 m/s
We can solve this problem by applying the principle of conservation of momentum.
It states that the total final momentum of a system is equal to the total initial momentum of the system.
M*U + m*u = M*V + m*v
Where u is the initial velocity of the pumpkin.
Since the final velocity of Brittany and the skateboard is equal to the final velocity of pumpkin:
M*U + m*u = (M + m) *v
Solving this to get u:
(62 * 0) + (3.7 * u) = (62 + 3.7) * 0.18
0 + 3.7u = 65.7 * 0.18
3.7u = 11.826
u = 11.826 / 3.7
u = 3.196 m/s
The initial velocity of the pumpkin was 3.196 m/s.
Answer: 8.81 J
Explanation: The scalar or dot product of 2 vector equals the product of the magnitude of both vectors and the cosine value of the angle between them
Magnitude of vector f (force) as given in the question = 12.5N
Magnitude of length = 0.75m
Angle between vectors = 25°
F. Δr = 12.5 * 0.75 * cos 25
F. Δr = 12.5 * 0.75 * 0.9063
F. Δr = 8.81 J
(a) The y-component or vertical velocity is calculated using:
Vy = Vsin(∅)
(b) The x-component or horizontal velocity is calculated using:
Vx = Vcos(∅)
A baseball traveling at 100 mph has more kinetic energy than a baseball traveling at 50 mph because the kinetic energy = 1/2 x mass x velocity. Since the baseballs should have the same mass, the velocity is what will determine which ball has more kinetic energy. Since the 100 mph baseball has a higher velocity than the 50 mph baseball, it has more kinetic energy.
From Largest to Smallest:
Earth > Biosphere > Biome > Ecosystem > Community > Population > Organism > Organelles
Hope this helps!
