Answer:
Explanation:
Most of this water is locked up in ice, and another 20.9% is found in lakes. Rivers make up 0.49% of surface freshwater. Although rivers account for only a small amount of freshwater, this is where humans get a large portion of their water from.
Answer:
Explanation:
1 ) Since it is a isochoric process , heat energy passed into gas
= n Cv dT , n is no of moles of gas , Cv is specific heat at constant volume and dT is rise in temperature .
= 7.4 x 12.47 x ( 500 - 300 )
= 18455.6 J.
2 ) Since there is no change in volume , work done by the gas is constant.
3 ) from , gas law equation
PV = nRT
P = nRT / V
= 7.4 x 8.3 x 500 / .74
= .415 x 10⁵ Pa.
4 ) Average kinetic energy of gas molecules after attainment of final temperature
= 3/2 x R/ N x T
= 1.5 x 1.38 x 10⁻²³ x 500
= 1.035 x 10⁻²⁰ J
1/2 m v² = 1.035 x 10⁻²⁰
v² = 2 x 1.035 x 10⁻²⁰ / 1.39 x 10⁻²⁶
= 1.49 x 10⁶
v = 1.22 x 10³ m /s
5 ) In this process , pressure remains constant
gas is cooled from 500 to 300 K
heat will be withdrawn .
heat withdrawn
= n Cp dT
= 7.4 x 20.79 x 200
= 30769.2 J .
6 )
gas will have reduced volume due to cooling
reduced volume = .74 x 300 / 500
= .444 m³
change in volume
= .74 - .444
= .296 m³
work done on the gas
= P x dV
pressure x change in volume
= .415 x 10⁵ x .296
= 12284 J.
Peer mediation is problem solving by youth with youth. It is a process by which two or more students involved in a dispute meet in a private, safe and confidential setting to work out problems with the assistance of a trained student mediator.
Answer:
Raising the highest point of the track to a higher point
Explanation:
When the rubber ball starts its motion, from the highest point of the track, it has only gravitational potential energy, given by:
where m is the mass of the ball, g is the gravitational acceleration and h is the height above the ground.
As the ball descends the track, this potential energy is partially converted into kinetic energy, given by:
(where m is the mass and v is the speed)
and partially lost as heat, due to the friction between the surface of the track.
As a consequence, the higher the initial height of the track (h in the formula), the greater will be the kinetic energy gained by the ball. A greater kinetic energy means a larger velocity, which also means that the ball will cover a longer distance before stopping.