Physics Answers

Suppose you have a 12.0V motorcycle battery that can move 5000C of charge and a 12.0V car battery that can move 60, 000C of charge. how much energy does each deliver? (Assume that the numerical value of each charge is accurate to three significant figures)

Helium is contained in a 3 𝑚3 rigid volume at 60℃ and 100 kPa. Find the heat transfer needed to increase the pressure to 1000 kPa.

The capacitors have values C1= 2.0 uf and C2= 4.0 uF, C3=5.0 uF C4= 7.0 uF and the potential difference across the battery is 9.0 V. Assume that the capacitors are connected in parallel?

A car is stopped at a traffic light. It then travels along a straight road such

that its distance from the light is given by:

𝑥(𝑡) = 2.4𝑡

2 − 0.120𝑡

3

Helium is contained in a 3 𝑚3 rigid volume at 60℃ and 100 kPa. Find the heat transfer needed to increase the pressure to 1000 kPa.

There are developed 10hp by a Carnot engine between 1000F and 100F.

Determine;

a. The thermal efficiency

b. The heat supplied per seconds

c. The change in entropy each second during heat rejection

A Carnot power cycle operates on 2lb/min of air between the limits of 70F and 500

F. The pressure at the beginning of isothermal expansions is 400 psia and at the end

of isothermal expansion 185.psig, determine;

a. The volume at the end of the isothermal compression

b. ∆S during an isothermal process

c. Qa, Qr, Wnet

d. Thermal efficiency

e. The mean effective pressure.

How much work is necessary to compress air in an insulated cylinder from 0.20 to 0.01

m3

. Use T1= 20C and P1= 100Kpa

A group of 50 persons attended a secret meeting in a room 12m x 10m x 3m high. The

room is completely sealed off and insulated. Each person gives off 150 kcal/hr of heat

and occupies a volume of 0.2 cubic meters. The room has an initial pressure of 101.3

kpa and 16C. calculate the room temp after 10minutes.

A vessel of 58L capacity is well insulated and is divided equally by a rigid conducting

diaphragm. Initially both halves contain air at pressure of 137.8 Kpa and 413.4 Kpa

and temperature of 27C and 177C respectively. Find the increase of entropy of the

system