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3 years ago

17

Physics

1 answer:

ivann1987 [24]3 years ago

3 0

Answer:

Heat energy required (Q) = 70,537.5 J

Explanation:

Given:

Mass of water (m) = 225 grams

Initial temperature of water = 25.0°C

Final temperature of water = 100.0°C

Specific heat of water (c) = 4.18 J/g

Find:

Heat energy required (Q)

Computation:

Change in temperature Δt = Final temperature of water - Initial temperature of water

Change in temperature Δt = 100 - 25

Change in temperature Δt = 75°C

Using Heat energy formula

Q = (m)(c)(Δt)

Heat energy required (Q) = (225)(4.18)(75)

Heat energy required (Q) = 70,537.5 J

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3 years ago

A net force of 24 N is acting on a 4.0-kg object. Find the acceleration in m/s2.

Inessa [10]

Hi there!

We can use Newton's Second Law:
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2 years ago

The Displacement is 5m. We found that using the

Llana [10]

Answer:

A vector can be written as:

(R, θ)

Where R is the magnitude, in this case, we know that the magnitude of the displacement is 5m

Then:

R = 5m

and θ defines the direction, it's an angle measured from the positive x-axis.

(In the image, θ would be the angle located at the point A)

Now, if you look at the image, you can see a triangle rectangle.

Where the adjacent cathetus has a length of 4,

the opposite cathetus has a length of 3 units

the hypotenuse has a length of 5 units.

So we can use any trigonometric rule to find the value of θ, like:

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Then:

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2 years ago

What is the mass of a ball that has 29j of potential energy and is lifted 2.0m?

Salsk061 [2.6K]

Answer:

1.48kg

Explanation:

Here,

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height (h) = 2m

acceleration due to gravity(g) =

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2 years ago

When running a half marathon (13.1 miles), it took Kevin 8 minutes to run from mile marker 1 to mile marker 2, and 18 minutes to

Vsevolod [243]

Answer:

It took Kevin 26 minutes to run from markers 1 to 4

His average speed from mile markers 1 to 4 is 0.154 miles/minute

Kevin must run by average speed 0.1 miles/minute to finish the race

Explanation:

Lets explain how to solve the problem

A half marathon 13.1 miles

Kevin took 8 minutes to run from mile marker 1 to mile marker 2 and

18 minutes to run from mile marker 2 to mile marker 4

→ He took 8 minutes and 18 minutes to run from marker 1 to marker 4

→ The total time of the first 4 marker = 8 + 18 = 26 minutes

It took Kevin 26 minutes to run from markers 1 to 4

Average speed is total distance divided by total time

The average speed of Kevin as he ran from mile marker 1 to mile

marker 4 is the 4 miles divides by 26 minutes

→ Average speed = 4 ÷ 26 = $\frac{2}{13}$ = 0.154 miles/minute

His average speed from mile markers 1 to 4 is 0.154 miles/minute

It took Kevin 71 minutes to pass mile marker 9

Kevin need to complete the race in 112 minutes, then what must

Kevin's average speed be as he travels from mile marker 9 to the

finish line?

The total distance of the race is 13.1 miles, he ran 9 miles

→ The remaining distance = 13.1 - 9 = 4.1 miles

He must run 4.1 miles to complete the race

The total time is 112 minutes, he used 71 minutes to run the first 9 miles

→ The remaining time = 112 - 71 = 41 minutes

He must finish the 4.1 miles in 41 minutes

→ His average speed for the last part of the race = 4.1 ÷ 41 = 0.1 mi/min

Kevin must run by average speed 0.1 miles/minute to finish the race

7 0

3 years ago

Read 2 more answers