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1 year ago

A runner of mass 80 kg is moving at 8.0 m/s. Calculate her kinetic energy.

Physics

1 answer:

lana [24]1 year ago

7 0

Answer:

2560J

Explanation:

By definition the kinetic energy can be calculated in the following way:

K = (mv²)/2 = 80kg·(8.0m/s)²/2 = 2560 J

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A sample of chloroform is found to contain 12.0 g of carbon, 106.4 g of chlorine, and 1.01 g of hydrogen. If a second sample of

GREYUIT [131]

Given:

Sample 1:

Chloroform is $CHCl_{3}$

12 g Carbon

1.01 g Hydrogen

106.4 g Cl

Sample 2:

30.0 g of Carbon

Solution:

mass of chloroform from sample 1:

12 + 1.01 +106.4 =119.41 g

Now, for the total mass of chloroform in sample 2:

mass of chloroform $\times$ $\frac{given mass of carbon}{mass of carbon atom}$

mass of chloroform = 119.41 $\times$ $\frac{30}{12}$ = 298.53 g

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2 years ago

A stable, binary ionic compound exists where the cation (A) has a charge twice in magnitude than that of the anion (X). What wou

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2 years ago

Read 2 more answers

A standing wave pattern is created on a string with mass density μ = 3.4 × 10-4 kg/m. A wave generator with frequency f = 61 Hz

uranmaximum [27]

Answer:

1) λ = 0.413 m , 2)v = 25,213 m / s , 3) T = 0.216 N , 4) m = 22.04 10-3 kg

Explanation:

1) The resonance occurs when the traveling wave bounces at the ends and the two waves are added, the ends as they are fixed have a node, the wavelength and the length of the string are related

λ = 2L / n n = 1, 2, 3 ...

In this case L = 0.62 m and n = 3

Let's calculate

λ = 2 0.62 / 3

λ = 0.413 m

2) the velocity related to wavelength and frequency

v = λ f

v = 0.413 61

v = 25,213 m / s

3) let's use the equation

v = √T /μ

T = v² μ

T = 25,213² 3.4 10⁻⁴

T = 0.216 N

4) the rope tension is proportional to the hanging weight

T-W = 0

T = W

W = m g

m = W / g

m = 0.216 / 9.8

m = 22.04 10-3 kg

5) n = 2

λ = 2 0.62 / 2

λ = 0.62 m

6) v = λ f

v = 0.62 61

v = 37.82 m / s

7) T = v² μ

T = 37.82² 3.4 10⁻⁴

T = 0.486 N

8) m = W / g

m = 0.486 / 9.8

m = 49.62 10⁻³ kg

9) n = 1

λ = 2 0.62

λ = 1.24 m

v = 1.24 61

v = 75.64 m / s

T = v² miu

T = 75.64² 3.4 10⁻⁴

T = 2.572 10⁻² N

m = 2.572 10⁻² / 9.8

m = 262.4 10⁻³ kg

5 0

2 years ago

A 100 kg box as showsn above is being pulled along the x axis by a student. the box slides across a rough surface, and its posit

Anit [1.1K]

Answer:

a) 2 m/s

b) i) $K.E = 50 (1.5t^2 + 2) ^2\\$

ii) $F = 3tm$

Explanation:

The function for distance is $x = 0.5t ^3 + 2t$

We know that:

Velocity = $v= \frac{d}{dt} x$

Acceleration = $a= \frac{d}{dt}v$

To find speed at time t = 0, we derivate the distance function:

$x = 0.5 t^3 + 2t\\v= x' = 1.5t^2 + 2$

Substitute t = 0 in velocity function:

$v = 1.5t^2 + 2\\v(0) = 1.5 (0) + 2\\v(0) = 2$

Velocity at t = 0 will be 2 m/s.

To find the function for Kinetic Energy of the box at any time, t.

$Kinetic \ Energy = \frac{1}{2} mv^2\\\\K.E = \frac{1}{2} \times 100 \times (1.5t^2 + 2) ^2\\\\K.E = 50 (1.5t^2 + 2) ^2\\$

We know that $Force = mass \times acceleration$

$a = v'(t) = 1.5t^2 + 2\\a = 3t$

$F = m \times a\\F= m \times 3t\\F = 3tm$

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3 years ago

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The startling answer is:

The bacteria ate the agar and reproduced (made more bacteria). There are so many of them now that you can see the blob of them.

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2 years ago

A runner of mass 80 kg is moving at 8.0 m/s. Calculate her kinetic energy. ​

A runner of mass 80 kg is moving at 8.0 m/s. Calculate her kinetic energy.