Answer:
18 miles
Explanation:
The average speed is 6 mph
Melanie ran for 3 hours
Speed × Time = Distance
So, 6 mph × 3 h = 18 miles
The heat energy which has to be supplied to change the state of a substance is called its latent heat. Latent heat does not increase the kinetic energy of the particles of the substance, so the temperature of a substance does not rise during the change of state. :))
Answer:
The average force the golf club exerts on the ball is 600 N
Explanation:
Newton's second law of motion states that force, F, is directly proportional to the rate of change of momentum produced
F = m× (v₂ - v₁)/(Δt)
The given parameters of the motion of the ball are;
The mass of the ball, m = 45 g = 0.045 kg
The initial velocity of the ball, v₁ = 0 m/s
The speed with which the ball was hit by the golfer, v₂ = 40 m/s
The duration of contact between the golf club and the ball, Δt = 3 ms = 0.003 seconds (s)
By Newton's law of motion, the average force, 'F', which the golf club exerts on the ball is therefore, given as follows;
F = 0.045 kg × (40 m/s - 0 m/s)/(0.003 s) = 600 N
The average force the golf club exerts on the ball = F = 600 N.
Answer:
Explanation:
18 km / h
= 300 m / min
12 km / h = 200 m / min
distance travelled in 200 minutes = 300 x 200 = 60000 m
distance travelled in 50 minute in return journey = 200 x 50 = 10000 m
total distance travelled = 70000 m
total time = 250 minute
speed = 70000 / 250
= 280 m / min
= 16.8 km / h
Total displacement = 60000 - 10000 = 50000 m
total time = 250 min
velocity = 50000 / 250
= 200 m / min
= 12 km / h
