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3 years ago

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Blythe and Geoff are ice-skating together. Blythe has a mass of 40 kg and Geoff has a mass of 79 kg. Blythe pushes Geoff in the

chest when both are at rest, causing him to move away at a speed of 5 m/s.

2 answers:

alexandr1967 [171]3 years ago

6 0

Answer:

Speed of Blythe is 9.8 m/s.

Explanation:

Mass of Blythe =40 kg

Mass of Geoff = 79 kg

Speed = 5 m/s

Suppose, we determine the Blythe's speed after she pushes Geoff

Since, initial momentum is zero final momentum should be zero.

Using momentum of conservation

$m_{B}v_{B}+m_{G}v_{G}=0$

$v_{B}=-\dfrac{m_{G}v_{G}}{m_{B}}$

Put the value into the formula

$v_{B}=-\dfrac{79\times5}{40}$

$v_{B}=-9.8\ m/s$

Negative sign shows that he move in direction opposite to Geoff.

Hence, Speed of Blythe is 9.8 m/s.

Deffense [45]3 years ago

4 0

9.9 m/s

calculations below

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BARSIC [14]

Answer:

The x component of the resultant force is -7.27N.

Explanation:

To obtain the x component of the resultant force, first we have to know the x components of the other forces. To do this, we just have to do some trigonometry:

$|F_{1x}|=|F_1|\cos\theta_1=9.20N\cos62.0\°=4.31N \\|F_{2x}|=|F_2|\cos\theta_2=5.00N\cos53.6\°=2.96N$

Since both vectors are in the left side of the y-axis, they have a negative x component. So:

$F_{1x}=-4.31N;\\F_{2x}=-2.96N$

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$F_{Rx}=-4.31N-2.96N=-7.27N$

In words, the x component of the resultant force is -7.27N.

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3 years ago

When a person stands on a rotating merry-go-round the frictional force?

wel

Answer. dry friction- <span> resists relative lateral motion of two solid surfaces in contact.</span>

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2 years ago

Coherent light of wavelength 540 nm passes through a pair of thin slits that are 3.4 × 10-5 m apart. At what angle away from the

Scrat [10]

Answer: $1.8\°$

Explanation:

The diffraction angles $\theta_{n}$ when we have a slit divided into $n$ parts are obtained by the following equation:

$dsin\theta_{n}=n\lambda$ (1)

Where:

$d=3.4(10)^{-5}m$ is the width of the slit

$\lambda=540 nm=540(10)^{-9}m$ is the wavelength of the light

$n$ is an integer different from zero.

Now, the second-order diffraction angle is given when $n=2$ , hence equation (1) becomes:

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Now we have to find the value of $\theta_{2}$ :

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Then:

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Finally:

$\theta_{2}=1.8\°$ (6)

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2 years ago

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Answer:

Explanation:

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lapo4ka [179]

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The force of gravity is always directed towards the centre of earth irrespective of the nature of applied force.

Hence, the direction of the gravitational force which acts on the box is vertically downward.

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3 years ago

Read 2 more answers