Because Any object or substance that is less dense than a fluid will float in that fluid, so hot water rises (floats) in colder water. When fluids are cooled, they contract and therefore become more dense. Any object or substance that is more dense than a fluid will sink in that fluid, so cold water sinks in warmer water
His weight depends on where he is, because
Weight = (mass) x (gravity in the place where the mass is) .
For example:
-- If this man is on Mars, his weight is (110 kg) x (3.7 m/s²) = 408 Newtons
-- If he is on the Moon, his weight is (110 kg) x (1.6 m/s²) = 176 Newtons
-- If he is on Earth, his weight is (110 kg) x (9.8 m/s²) = 1,078 Newtons
-- If he is in a spacecraft coasting from one to another, his weight is zero.
Answer: 9.9%
Explanation: efficiency = (work output /work input) × 100
Note that, 1 kilocalorie = 4184 joules, hence 22kcal = 22× 4184 = 92048 joules.
Work output = 9200 j and work input = 92048 j
Efficiency = (9200/92048) × 100 = 0.099 × 100 = 9.9%
Expression to calculate energy from voltage: E= V*Q where E= energy, V= voltage, and Q= charge
Additional help:
-To find the Voltage ( V )
[ V = I x R ] V (volts) = I (amps) x R (Ω)
-To find the Current ( I )
[ I = V ÷ R ] I (amps) = V (volts) ÷ R (Ω)
-To find the Resistance ( R )
[ R = V ÷ I ] R (Ω) = V (volts) ÷ I (amps)
I hope that helps to some extent-
Answer:
b. The normal force between the molecules of the paper is overcome by the contact force of the hands.
Explanation:
The paper molecules are held together by a weak bond. When the student holds the paper on both sides with the center of the paper in between, the student applies two equal forces in the opposite direction of the paper making the paper molecules weaken and separate.
