Answer:
A. nuclear fusion reactions
C. it's still hot from the big bang
Explanation:
The inside of the earth is hot due to some reasons. This heat provides the internal energy the drives processes within the earth interior. Here are some of the ways in which the heat has accumulated:
- Nuclear reactions within the earth interior by fusion and other radioactive processes releases a large amount of heat.
- Some heat accreted during the early formation of the earth and has not been lost till this day.
- Heating due to friction
These are some of the sources of the earth's internal heat.
Answer:
You pull on the oars. By the third law, the oars push back on your hands, but that’s irrelevant to the motion of the boat. The other end of each oar (the blade) pushes against the water. By the third law, the water pushes back on the oars, pushing the boat forward.
Answer:
38.4 m/s
Explanation:
a) at t = 3.2s. 
b) at t = 3.2 + Δt. 
c) As Δt approaches 0. We can find the velocity by the ratio of Δx/Δt






As Δt approaches 0, v = 38.4 + 0 = 38.4 m/s
Answer:
K =6.697 Kg/s²
Explanation:
Given:
delta m =41 g = 0.041 kg
delta x = 6cm = 0.06m
g = 9.8 m/s²
according to the given formula
K = delta m g /delta x
K = (0.041 kg × 9.8 m/s²) / 0.06m
K =6.697 Kg/s²