Answer:
Systems always tend toward a state of decreasing order unless more energy is provided into the system to counteract this tendency.
Answer: Rn :)))) no explanation needed
Radiation: Getting sunburnt on a beach.
- The sun’s radiation (no direct contact) is what causes the skin to burn.
Radiation: Microwave cooking food
- Microwaves use radiation to heat the food inside of it; between radio waves and infrared radiation on the electromagnetic spectrum
Conduction: Touching a hot car seat in the summer
- Conduction is the transfer of heat by direct contact (hand to seat).
Conduction: Burning yourself with a curling iron (Similar to above; direct contact).
Convection: An ocean breeze
- Convection near coastlines cause the transfer of energy; water warms and cools slower than land.
Conduction: Sliding down a hot metal slide in august
- You are in direct contact with the slide, which is hot due to the temperature.
Convection: Water in a boiling pot of macaroni
- The water, a liquid, is being heated by molecular motion.
Convection: Currents deep within the earth that cause tectonic plates to move
- Convection currents drive the movement of tectonic plates in the mantle, which is fluid/molten. The currents circulate under the asthenosphere.
Answer: Speed = 4 m/s
Explanation:
The parameters given are
Mass M = 60 kg
Height h = 0.8 m
Acceleration due to gravity g= 10 m/s2
Before the man jumps, he will be experiencing potential energy at the top of the table.
P.E = mgh
Substitute all the parameters into the formula
P.E = 60 × 9.8 × 0.8
P.E = 470.4 J
As he jumped from the table and hit the ground, the whole P.E will be converted to kinetic energy according to conservative of energy.
When hitting the ground,
K.E = P.E
Where K.E = 1/2mv^2
Substitute m and 470.4 into the formula
470.4 = 1/2 × 60 × V^2
V^2 = 470.4/30
V^2 = 15.68
V = square root (15.68)
V = 3.959 m/s
Therefore, the speed of the man when hitting the ground is approximately 4 m/s