Answer:
A. 456 seconds
Explanation:
We are given that two students walk in the same direction along a straight path at a constant speed.
One student walks with a speed=0.90 m/s
second student walks with speed=1.9 m/s
Total distance covered by each students=780 meter
We have to find who is faster and how much time extra taken by slower student than the faster student.
Time taken by one student who travel with speed 0.90 m/s=
Time=
Time taken by one student who travel with speed 0.90 m/s
=
Time taken by one student who travel with speed 0.90 m/s
=866.6 seconds
Time taken by second student who travel with speed 1.9 m/s=
=410.5 seconds
The second student who travels with speed 1.9 m/s is faster than the student travels with speed 0.90 m/s .
Extra time taken by the student travels with speed 0.90 m/s=866.6-410.5=456.1 seconds
Extra time taken by the student travels with speed 0.90 m/s=456 seconds
Hence, option A is true.

1. According to person standing on ground ~
2. According to The car ~
- The person is not in motion
3. According to the Seat ~
- The person is not in motion
4. According to another person on ride ~
- The person is not in motion
5. According to the track ~
6. According to the Sun ~
I hope that's what you were looking for, goodluck for your assignment ~
Answer: Power is 200 W
Explanation: Power P = work done / time used.
P = W/t = mgh/t = 154 kg · 9.81 m/s²· 4 m / 30 s = 201 W
The important point here is that volumetric flow rate in the pump and the pipe is the same.
Q = AV, where Q = Volumetric flow rate, A = Cross sectional area, V = velocity
Q (pump) = (π*15^2)/4*2 = 353.43 cm^3/s
Q (pipe) = (π*(3/10)^2)/4*V = 0.071V
Q (pump) = Q (pipe)
0.071V = 353.43 => V = 5000 cm/s
Therefore, the flow of water in the pipe is 5000 cm/s.
Answer:
a. burning of fossil fuel
Explanation:
Greenhouse effect is the trapping of the sun infrared rays in the outermost layer of the earths atmosphere due to the accumulation of some harmful gasses. This gases depletes the ozone layer
The major contributor of greenhouse gases is the burning of fossil fuels. Carbon dioxides are released into the atmosphere and leads to global warming and climatic changes per time