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3 years ago

If a 25 kg lawnmower produces 347 w and does 9514 J of work, for

Physics

1 answer:

Igoryamba3 years ago

6 0

Steps 1 and 2)

The variables are W = work, P = power, and t = time. In this case, W = 9514 joules and P = 347 watts.

The goal is to solve for the unknown time t.

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Step 3)

Since we want to solve for the time, and we have known W and P values, we use the equation t = W/P

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Step 4)

t = W/P

t = 9514/347

t = 27.4178674351586

t = 27.4 seconds

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Step 5)

The lawn mower ran for about 27.4 seconds. I rounded to three sig figs because this was the lower amount of sig figs when comparing 9514 and 347.

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Note: we don't use the mass at all

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3 years ago

If a car travels 30 mi. north for 30 min., 60 mi. east for 1.0 hour, and 30 mi. south for 30 min., what is the average speed

Ainat [17]

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Given the following :

First leg travel:

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Time of travel= 30 minutes = 0.5 hour

Second leg travel:

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Speed = total Distance / time of travel

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4 years ago

A tank contains gas at 13.0°C pressurized to 10.0 atm. The temperature of the gas is increased to 95.0°C, and half the gas is re

fomenos

Answer:

The pressure of the remaining gas in the tank is 6.4 atm.

Explanation:

Given that,

Temperature T = 13+273=286 K

Pressure = 10.0 atm

We need to calculate the pressure of the remaining gas

Using equation of ideal gas

$PV=nRT$

For a gas

$P_{1}V_{1}=nRT_{1}$

Where, P = pressure

V = volume

T = temperature

Put the value in the equation

$10\times V=nR\times286$ ....(I)

When the temperature of the gas is increased

Then,

$P_{2}V_{2}=\dfrac{n}{2}RT_{2}$ ....(II)

Divided equation (I) by equation (II)

$\dfrac{P_{1}V}{P_{2}V}=\dfrac{nRT_{1}}{\dfrac{n}{2}RT_{2}}$

$\dfrac{10\times V}{P_{2}V}=\dfrac{nR\times286}{\dfrac{n}{2}R368}$

$P_{2}=\dfrac{10\times368}{2\times286}$

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3 years ago

You run away from a plane mirror at 2.30 m/s. At what speed does your image move away from you?

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Answer:

4.60m/s

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3 years ago

Examine the scenario.

vovangra [49]

Answer:

acceleration 8 km/h/s south

Explanation:

First of all, let's remind that a vector quantity is a quantity which has both a magnitude and a direction.

Based on this definition, we can already rule out the following two choices:

distance: 40 km

speed: 40 km/h

Since they only have magnitude, they are not vectors.

Then, the following option:

velocity: 5 km/h north

is wrong, because the car is moving south, not north.

So, the correct choice is

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In fact, the acceleration can be calculated as

$a=\frac{v-u}{t}$

where

v = 40 km/h is the final velocity

u = 0 is the initial velocity

t = 5 s is the time

Substituting,

$a=\frac{40 km/h-0}{5 s}=8 km/h/s$

And since the sign is positive, the direction is the same as the velocity (south).

7 0

3 years ago