An object is placed beyond the focal point on the principal axis of a concave mirror, the image will be

Two workers are sliding 300 kg crate across the floor. One worker pushes forward on the crate with a force of 400 N while the ot

almond37 [142]

Answer:

The kinetic coefficient of friction of the crate is 0.235.

Explanation:

As a first step, we need to construct a free body diagram for the crate, which is included below as attachment. Let supposed that forces exerted on the crate by both workers are in the positive direction. According to the Newton's First Law, a body is unable to change its state of motion when it is at rest or moves uniformly (at constant velocity). In consequence, magnitud of friction force must be equal to the sum of the two external forces. The equations of equilibrium of the crate are:

$\Sigma F_{x} = P+T-\mu_{k}\cdot N = 0$ (Ec. 1)

$\Sigma F_{y} = N - W = 0$ (Ec. 2)

Where:

$P$ - Pushing force, measured in newtons.

$T$ - Tension, measured in newtons.

$\mu_{k}$ - Coefficient of kinetic friction, dimensionless.

$N$ - Normal force, measured in newtons.

$W$ - Weight of the crate, measured in newtons.

The system of equations is now reduced by algebraic means:

$P+T -\mu_{k}\cdot W = 0$

And we finally clear the coefficient of kinetic friction and apply the definition of weight:

$\mu_{k} =\frac{P+T}{m\cdot g}$

If we know that $P = 400\,N$ , $T = 290\,N$ , $m = 300\,kg$ and $g = 9.807\,\frac{m}{s^{2}}$ , then:

$\mu_{k} = \frac{400\,N+290\,N}{(300\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)}$

$\mu_{k} = 0.235$

The kinetic coefficient of friction of the crate is 0.235.

5 0

3 years ago

Melting ice caps can result in _____.

IceJOKER [234]

Melting of ice caps ... causing them to shrink in coverage .. can result in ...

-- wet ground

-- more farming opportunities, but less skiing

-- higher sea level

-- coastal flooding

-- extinction of plant and animal species

-- more icebergs floating around

-- lower average albedo, higher solar absorption, widespread warming

4 0

3 years ago

Read 2 more answers

What are the two key elements needed for fossilization

xenn [34]

Body Fossils and Trace Fossils.

Hope I helped and good luck with school. Bye!

3 0

4 years ago

A circular coil with 600 turns has a radius of 15 cm. The coil is rotating about an axis perpendicular to a magnetic field of 0.

Reil [10]

Answer:

The angular frequency is the coil rotating is 1.9 rad/s.

Explanation:

Given that,

Number of turns = 600

Radius = 15 cm

Magnetic field = 0.020 T

Maximum induced emf = 1.6 V

We need to calculate the angular frequency is the coil rotating

Using formula emf

$\epsilon =NBA\omega\sin\omega t$

When induced emf is maximum so $\sin\omega t$ will be 1.

$\omega=\dfrac{\epsilon}{NBA}$

Where, N = number of turns

A = area

B = magnetic field

Put the value into the formula

$\omega=\dfrac{1.6}{600\times\pi\times(15\times10^{-2})^2\times0.020}$

$\omega=1.9\ rad/s$

Hence, The angular frequency is the coil rotating is 1.9 rad/s.

6 0

3 years ago

Which sea creature has three hearts?

storchak [24]

Octopus

1. Octopus/Squid. These similar creatures are both cephalopods and have three hearts in total, one systematic to go along with two “gill hearts” that force blood to the gills.

Hope This Helps! Have a Nice Day!!

3 0

3 years ago

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