Answer:The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener.
As the source of sound waves approaches a listener, the sound waves get closer together, increasing their frequency and the pitch of the sound. The opposite happens when the source of sound waves moves away from the listener.
Explanation:
Distance = speed x time. The total speed is 30 + 60 = 90km/h and the total time taken is 15 + 15 = 30 minutes. Therefore, you do 90 x 30 = 2700km
Answer = 2700km
Answer:
Exerxingtransforms the chemical energy in the food you eat into Kinetic Energy.
Therefore, the answer is A. Kinetic Energy
Answer:
The acceleration is 0.133 m/s²
The time taken to build the final speed is 219.32 s
Explanation:
Given;
final speed of the cyclist, v = 105 km/h = 29.17 m/s²
distance traveled by the cyclist, d = 3.2 km = 3,200 m
initial speed, u = 0
Apply the following kinematic equation to determine the acceleration of the cyclist;
v² = u² + 2as
(29.17 )² = 0 + (2 x 3200)a
850.89 = 6400a
a = (850.89 ) / (6400)
a = 0.133 m/s²
The time taken to build up the final speed is given by;
v = u + at
29.17 = 0 + (0.133)t
t = 29.17 / 0.133
t = 219.32 s
Answer:
The efficiency of this engine is 37.63 %.
Explanation:
Given;
useful output work done by the combustion engine, = 356 kJ
input work, = 946 kJ
The efficiency of the combustion engine is calculated as;

Therefore, the efficiency of this engine is 37.63 %.