Answer: His average speed in mph over the last 400 m is 7.7 m/s.
Explanation:
Given: Hicham El Guerrouj of Morocco holds the world record in the 1500 m running race. He ran the final 400 m in a time of 51.9 s.
We know that , speed =
Here , distance = 400m and time = 51.9 s
Then, speed =
Hence, his average speed in mph over the last 400 m is 7.7 m/s.
I am guessing the answer to your question, is calories.
Answer:
Explanation:
Radius of the ball is
Initial speed of the ball is
Initial angular speed of the ball is
Coefficient of kinetic friction between the ball and the lane
is
Due to the presence of frictional force, ball moves with
decreasing velocity.
(a)
velocity in terms of is
(b)
Ball's linear acceleration is given by
(c)
During sliding, ball's angular acceleration is calculated as
(d)
The time for which the ball slides is calculated from the
equation of motion is
(e)
Distance traveled by the ball is
(for)
The speed of the ball when smooth rolling begins is
Answer:
a) 1511 MW
b) 44%
Explanation:
The thermal power will be the electric power plus the heat taken away by the cooling water.
Qt = P + Qc
The heat taken away by the water will be:
Qc = G * Cp * (t1 - t0)
The Cp of water is 4180 J/(kg K)
The density of water is 1 kg/L
Then
G = 1.17 * 10^8 L/h * 1 kg/L * 1/3600 h/s = 32500 kg/s
Now we calculate Qc
Qc = 32500 * 4180 * (29.8 - 23.6) = 842*10^6 W = 842 MW
The total thermal power then is
Qt = 669 + 842 = 1511 MW
The efficiency is
η = P / Qt
η = 669 / 1511 = 44%