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2 years ago

Pls someone help me with this :(

Physics

1 answer:

RUDIKE [14]2 years ago

6 0

4.0 is gonna be your answer

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A hockey pick sliding along a frictional surface strikes a box at rest, after the collision the two objects stick together and m

Hitman42 [59]

Answer:

Explanation:

Option a is correct

If puck and pick constitute a system then the momentum of the system is conserved but not this may not be valid for the puck .

Option e is correct

If puck and pick is the system then momentum is conserved but because of the presence of friction, mechanical energy is not conserved.

Friction will cause the energy to dissipate in heat.

5 0

2 years ago

..................,,,,,,,,,

Fiesta28 [93]

Answer:

.....,.,.,.,.,.,.,.,.,.,.,.,..,.,.,.,.,.,.,,.,.┌(・。・)┘♪

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2 years ago

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The height of a typical playground slide is about 1.8 m and it rises at an angle of 30 ∘ above the horizontal.

Salsk061 [2.6K]

Answer:

$5.94\ \text{m/s}$

$1.7$

$0.577$

Explanation:

g = Acceleration due to gravity = $9.81\ \text{m/s}^2$

$\theta$ = Angle of slope = $30^{\circ}$

v = Velocity of child at the bottom of the slide

$\mu_k$ = Coefficient of kinetic friction

$\mu_s$ = Coefficient of static friction

h = Height of slope = 1.8 m

The energy balance of the system is given by

$mgh=\dfrac{1}{2}mv^2\\\Rightarrow v=\sqrt{2gh}\\\Rightarrow v=\sqrt{2\times 9.81\times 1.8}\\\Rightarrow v=5.94\ \text{m/s}$

The speed of the child at the bottom of the slide is $5.94\ \text{m/s}$

Length of the slide is given by

$l=h\sin\theta\\\Rightarrow l=1.8\sin30^{\circ}\\\Rightarrow l=0.9\ \text{m}$

$v=\dfrac{1}{2}\times5.94\\\Rightarrow v=2.97\ \text{m/s}$

The force energy balance of the system is given by

$mgh=\dfrac{1}{2}mv^2+\mu_kmg\cos\theta l\\\Rightarrow \mu_k=\dfrac{gh-\dfrac{1}{2}v^2}{gl\cos\theta}\\\Rightarrow \mu_k=\dfrac{9.81\times 1.8-\dfrac{1}{2}\times 2.97^2}{9.81\times 0.9\cos30^{\circ}}\\\Rightarrow \mu_k=1.73$

The coefficient of kinetic friction is $1.7$ .

For static friction

$\mu_s\geq\tan30^{\circ}\\\Rightarrow \mu_s\geq0.577$

So, the minimum possible value for the coefficient of static friction is $0.577$ .

8 0

2 years ago

ithout heat from the Sun, the water cycle would A) reverse. B) not work. C) slow down. D) not be affected.

lawyer [7]

B) Not work since decrease in temperature wouldnt cause evaporation or reverse in cycle.

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3 years ago

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Describe what happens when electrical impulses cross muscle fibers

kaheart [24]

Answer:

Sometimes may cause involuntary responses like twitching

Explanation:

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3 years ago