Answer:
Explanation:
From the question, it says that their tent is 11 km away from the shore which is also 3 km away from the coral reef. Essentially, the tent us 11 + 3 km away from the coral reef, and that's 14 km. He has to run at a rate of 7 know to cover an 11 km length and swim at 2 kmph to cover a 3 km length.
All the visitor needs to do is run more than 7 kmph to reduce the days time. For example, running at 11 kmph takes him or her exactly 1 hour to reach the shore, before taking another swim of about an hour to reach the reef
Answer:
290
Explanation:
Average acceleration is the change in velocity over change in time.
First, find the velocity by taking the derivative of position.
v(t) = dx/dt
v(t) = 38t + 21t²
At t = 3 and t = 9:
v(3) = 303
v(9) = 2043
So the average acceleration is:
a = Δv / Δt
a = (2043 − 303) / (9 − 3)
a = 290
Use appropriate units.
Answer:
Diathermy and atmospheric pressure
Explanation:
When the energy from the Sun comes to the Earth, it hits first the atmosphere, but the air contained is almost unaffected by it because the molecules are not tight enough to absorb its incoming energy.
Later on, the sunlight reaches the soil, thus absorbing part of the energy and reflecting the rest. Because of this reflection, the air near to the ground begins to heat through convection and as it gains height the air pressure (thus the air molecules begin to separate more from each other) decreases and the energy transfer to them is more difficult. As a result, as you gain height, the air temperature decreases at a rate of 6.8 ºC every 1,000 meters.