A wheel rotates at 24 revolutions every 3 minutes. This is equivalent to

Find the kenetic energy of a car of mass 700kg racing with a velocity of 10m/s

fiasKO [112]

Answer:

35000 KJ

Explanation:

The equation for the kinetic energy is given by the formula :

$E_{k} = \frac{1}{2} mv^{2}$

$E_{k} = \frac{1}{2} (700)(10)^{2}$

$E_{k} = \frac{1}{2} (700)(100)$

$E_{k} = (350)(100)$ OR $E_{k} = \frac{1}{2} (70000)$

$E_{k} = 35000$

Units will be kilojoules since the units of mass was kilograms .

Our final answer is 35000 KJ

Hope this helped and have a good day

5 0

2 years ago

A plane accelerates from rest at a constant rate of 5.00 m/s2 along a runway that is 1800 m long. Assume that the plane reaches

tiny-mole [99]

Answer:

26.8 seconds

Explanation:

To solve this problem we have to use 2 kinematics equations: *I can't use subscripts for some reason on here so I am going to use these variables:

v = final velocity

z = initial velocity

x = distance

t = time

a = acceleration

${v}^{2} = {z}^{2} + 2ax$

$v = z + at$

First let's find the final velocity the plane will have at the end of the runway using the first equation:

${v}^{2} = {0}^{2} + 2(5)(1800)$

$v = 60 \sqrt{5}$

Now we can plug this into the second equation to find t:

$60 \sqrt{5} = 0 + 5t$

$t = 12 \sqrt{5}$

Then using 3 significant figures we round to 26.8 seconds

3 0

3 years ago

A rock is being twirled in a circle on the end of a string. The string provides the centripetal force needed to keep the ball mo

KonstantinChe [14]

Answer:

No

Explanation:

The force of tension exerted by the string on the rock acts as centripetal force, so its direction is always towards the centre of the circle.

However, the direction of motion of the rock is always tangential to the circle: this means that the force is always perpendicular to the direction of motion of the rock.

As we know, the work done by a force on an object is

$W=Fd cos \theta$

where

F is the magnitude of the force

d is the displacement of the object

$\theta$ is the angle between the force and the displacement

In this situation, F and d are perpendicular, so $\theta=90^{\circ}$ , therefore $cos \theta = 0$ and the work done is zero:

$W=0$

4 0

3 years ago

It is generally seen that, when a substance absorbs heat energy, its heating curve shows two plateaus. Which phenomenon is indic

Tatiana [17]

Answer:

The correct answer is;

Change of phase.

Explanation:

When the physical state in which a substance exists in nature changes to another physical state such as a change from solid state to a liquid stat or from a liquid state to a gaseous state, the substance is said to have undergone a phase change, or phase transformation.

The state of a substance will change, depending on the surrounding temperature and the applied pressure and the energy required for the substance to change its state is known as latent heat.

The observed plateaus are periods the latent heat is absorbed to completely change the phase of the substance.

5 0

3 years ago

Sliding friction is affected by the weight of the object.<br><br> True or false

Dmitry [639]

Yes that is correct or in other form, True

7 0

3 years ago

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