A 50n box is lifted 2 meters in 3 seconds.

A ferris wheel has a radius of 36 feet and completes one revolution every 5.4 minutes. what is the speed of the ferris wheel (in

KIM [24]

In order to find the speed per minute you will have to divide the two numbers together. You need to do 36/5.4 so the answer will be around 6.7 feet per minute.

4 0

3 years ago

I need to present a proposal for a device that minimizes heat transfer. I need help PLEASE

eimsori [14]

Engineers must understand the thermal properties of materials to be able to predict the performance of any given material over its lifetime in a specific application. Engineers apply their understanding of the thermal properties of materials to the design of efficient heat transfer materials for better engines, spacecraft and electronic devices. They also examine the thermal properties of insulation to design more efficient buildings and homes. Engineers develop ways to minimize heat transfer from a motor to the surrounding environment. Often they find ways to insulate the motor to decrease the convective heat transfer from the motor. They design a refrigerator to keep heat out of the inside, as well as keep the refrigerator contents cool. hope this helped

3 0

4 years ago

A rigid container holds 0.30g of hydrogen gas.

Strike441 [17]

Answer:

Part A: $\mathbf{Q =94 \ J}$ to two significant figures

Part B: $\mathbf{Q =160 \ J}$ to two significant figures

Part C: $\mathbf{Q =220 \ J}$ to two significant figures

Explanation:

Given that :

mass of the hydrogen = 0.30 g

the molar mass of hydrogen gas molecule = 2 g/mol

we all know that:

number of moles = mass/molar mass

number of moles = 0.30 g /2 g/mol

number of moles = 0.15 mol

For low temperature between the range of 50 K to 100 K, the specific heat at constant volume for a diatomic gas molecule = $C_v=\dfrac{3}{2}R$

For Part A:

$Q = mC_v\Delta T$

$Q= 0.15 \ mol (\dfrac{3}{2})(8.314 \ J/mole.K )(100-50)K$

$Q= 0.15 \times (\dfrac{3}{2}) \times (8.314 \ J )\times (50)$

$Q=93.5325 \ J$

$\mathbf{Q =94 \ J}$ to two significant figures

Part B. For hot temperature, $C_v=\dfrac{5}{2}R$

$Q = mC_v\Delta T$

$Q= 0.15 \ mol (\dfrac{5}{2})(8.314 \ J/mole.K )(300-250)K$

$Q= 0.15 \times (\dfrac{5}{2}) \times (8.314 \ J )\times (50)$

$Q=155.8875 \ J$

$\mathbf{Q =160 \ J}$ to two significant figures

Part C. For an extremely hot temperature, $C_v=\dfrac{7}{2}R$

$Q = mC_v\Delta T$

$Q= 0.15 \ mol (\dfrac{7}{2})(8.314 \ J/mole.K )(2300-2250)K$

$Q= 0.15 \times (\dfrac{7}{2}) \times (8.314 \ J )\times (50)$

$Q=218.2425 \ J$

$\mathbf{Q =220 \ J}$ to two significant figures

6 0

3 years ago

We can use energy principles to make ____ predictions.

stira [4]

Compatible and speedy

5 0

3 years ago

What is the speed of a car traveling 100 m in 20 s?

Ludmilka [50]

Answer: To answer this question, we will need the following equation: SPEED = DISTANCE/TIME (A multiplication and division triangle will be shown)i) The speed of the car is calculated by doing 100 metres/ 20 seconds which gives us 5 metres per second. ii) Rearranging the equation earlier, we can make the distance the subject of the equation so that we get SPEED x TIME = DISTANCE. We worked out the speed and the time was given as 1 minute 40 seconds but we cannot plug in the numbers yet as the time has to be converted to units of seconds (because our speed is in meters per second). 1 minute 40 seconds = 60 seconds + 40 seconds = 100 secondsWe then plug in the numbers to get the distance travelled = 5 metres per second x 100 seconds = 500 metres.

Explanation:

3 0

3 years ago