Answer:
when we lower a bucket into a well to fetch water, the work done by gravity is positive since force and displacement are in the same direction.
Explanation:
Answer:
1.64 * 10^(-5) m
Explanation:
Parameters given:
Angular separation, θ = 0.018 rad
Wavelength, λ = 589 nm = 5.89 * 10^(-7) m
The angular separation when there are 2 slots is given as
θ = λ/2d
where d = separation between slits
d = λ/2θ
d = (589 * 10^(-9))/(2 * 0.018)
d = 1.64 * 10^(-5) m
When you climb, earth exerts gravitational force on pack in downward direction(pointing towards the center of earth).
In order to climb, you need to work against work done by gravity on the pack.
Hence work done by you = work done by gravity on pack
= Force x displacement = 70 x 30 = 2100 J.
So you need to do 2100 joules of work to lift your pack.
Power is the rate of work done.
Therefore power = work done by you/time(in seconds)
= 2100/600 =3.5 watts
Answer:
It takes millions sometimes hundreds of millions Explanation:
Answer: Neon is a colorless gas at room temperature: Physical property
At room temperature, mercury is a liquid: Physical property
Apple slices turn brown when exposed to air: Chemical property
Phosphorus will ignite when exposed to air: Chemical property
Explanation:
Physical property is defined as the property of a substance which becomes evident during physical change in which there is alteration in shape, size etc. No new substance gets formed during physical change.
Example: Neon is a colorless gas at room temperature
At room temperature, mercury is a liquid.
Chemical property is defined as the property of a substance which becomes evident during chemical change in which a change in chemical composition takes place. A new substance is formed in these reactions.
Example: Apple slices turn brown when exposed to air: It undergoes oxidation which is a chemical change
Phosphorus will ignite when exposed to air: It undergoes oxidation which is a chemical change
