A 1 500-kg car is moving at 20.0 m/s. The driver brakes to a stop. The brakes cool off to the temperature of the surrounding air, which is nearly constant at 20.0$^ { \circ } \mathrm { C }$. What is the total entropy change?

What change in entropy occurs when a 27.9-g ice cube at −12$^ { \circ } \mathrm { C }$ is transformed into steam at 115$^ { \circ } \mathrm { C }$?

Assume that the probability that the air brakes on large trucks will fail on a particularly long downgrade is .001. Assume also that the emergency brakes on such trucks can stop a truck on this downgrade with probability .8. These braking systems operate independently of one another. Find the probability that

(a) the air brakes fail but the emergency brakes can stop the truck

(b) the air brakes fail and the emergency brakes cannot stop the truck

(c) the emergency brakes cannot stop the truck given that the air brakes fail

Dimensions of a centrifugal pump impeller are

$$\begin{matrix} \text{Parameter} & \text{Inlet, Section 1} & \text{Outlet, Section 2}\\ \text{Radius, r (mm)} & \text{175} & \text{500}\\ \text{Blade width, b (mm)} & \text{50} & \text{30}\\ \text{Blade angle, }{\beta (deg)} & \text{65} & \text{70}\\ \end{matrix}$$

The pump handles water and is driven at 750 rpm. Calculate the theoretical head and mechanical power input if the flow rate is 0.75 $\mathrm{m}^{3}$/s. For the impeller, operating at 750 rpm, determine the volume flow rate for which the tangential component of the inlet velocity is zero. Calculate the theoretical head and mechanical power input.

A 750-kg car moving at 23 m/s brakes to a stop. The brakes contain about 15 kg of iron, which absorbs the energy. What is the increase in temperature of the brakes?

A sample consisting of 3.00 mol of diatomic perfect gas molecules at 200 K is compressed reversibly and adiabatically until its temperature reaches 250 K. Given that $C_{V, {~m}}=27.5 {~J} {~K}^{-1} {~mol}^{-1}$, calculate $q, w, \Delta U, \Delta H$, and $\Delta S$.

A sample consisting of 2.00 mol of diatomic perfect gas molecules at 250 K is compressed reversibly and adiabatically until its temperature reaches 300 K. Given that $C_{V, {~m}}=27.5 {~J} {~K}^{-1} {~mol}^{-1}$, calculate $q, w, \Delta U, \Delta H$, and $\Delta S$.

A Styrofoam cup holding 125 g of hot water at $1.00 \times 10 ^ { 2 \circ } \mathrm { C }$ cools to room temperature, 20.0 $^ { \circ }$. What is the change in entropy of the room? (Neglect the specific heat of the cup and any change in temperature of the room.)

The temperature at the surface of the Sun is approximately $5700 \mathrm{~K}$, and the temperature at the surface of the Earth is approximately $290 \mathrm{~K}$. What entropy change occurs when $1000 \mathrm{~J}$ of energy is transferred by radiation from the Sun to the Earth?

With air brake vehicles, the parking brakes should be used:

An object disintegrates into two fragments. One fragment has mass 1.00 MeV/c2 and momentum 1.75 MeV/c in the positive x direction, and the other has mass 1.50 MeV/c2 and momentum 2.00 MeV/c in the positive y direction. Find (a) the mass and (b) the speed of the original object.

An ideal gas is taken through a Carnot cycle. The isothermal expansion occurs at 250$^ { \circ } \mathrm { C }$, and the isothermal compression takes place at 50.0$^ { \circ } \mathrm { C }$. The gas takes in $1.20 \times 103$ J of energy from the hot reservoir during the isothermal expansion. Find the net work done by the gas in each cycle.

________memory is a subdivision of declarative memory that is concerned with general knowledge and facts.

The air you breathe is composed of about $20 \%$ oxygen and $80 \%$ nitrogen. Which atomic window best represents a sample of air?

At sea level the composition of the atmosphere is approximately 80 per cent nitrogen and 20 per cent oxygen by mass. At what height above the surface of the Earth would the atmosphere become 90 per cent nitrogen and 10 per cent oxygen by mass? Assume that the temperature of the atmosphere is constant at $25^{\circ} \mathrm{C}.$ What is the pressure of the atmosphere at that height?