Answer:
a)= 98kJ
b)=108kJ
c) = 10kJ
Explanation:
a. The work that is done by gravity on the elevator is:
Work = force * distance
= mass * gravity * distance
= 1000 * 9.81 * 10
= 98,000 J
= 98kJ
b)The net force equation in the cable
T - mg = ma
T = m(g+a)
T = 1000(9.8 + 10)
T = 10800N
The work done by the cable is
W = T × d
= 10800N × 10
= 108000
=108kJ
c) PE at 10m = 1000 * 9.81 * 10 = 98,100 J
Work done by cable = PE +KE
108,100 J = KE + 98,100 J
KE = 10,000 J
= 10kJ
=
Previous rocks melt and collide and to form igneous rocks.
Igneous rocks disintegrate due to weather disruptions and get carried away by water, where they form sedimentary rock strata by lithification.
Igneous and sedimentary change by heat and pressure to form metamorphic rocks.
Metamorphic rocks melt and become igneous rocks.
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.