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3 years ago

What is the velocity of an object with a kinetic energy of 800 J and a mass of 12 kg?

Physics

1 answer:

Elis [28]3 years ago

3 0

K.E = 1/2 mv²

800 = 1/2 ×12 ×v²

800 = 6 v²

800 / 6 = v²

= 133.4 =v²

√133.4 = √v²

11.5 = v²

I hope this answer is correct.

You might be interested in

According to the law of conservation of energy, which statement must be true?

Nitella [24]

Answer:

B. A system cannot take in additional matter.

Explanation: The total amount of energy in the universe remains constant, it can merely change from one form to another.

Hope it helps you:)))

have a good day

5 0

2 years ago

A electric heater that draws 13.5 a of dc current has been left on for 10 min. how many electrons that have passed through the h

kicyunya [14]

By definition, Ampere is a unit of current which is a measure of the amount of charge passing through a point in a circuit per unit of time, with an equivalent charge of 1.602 x 10^(-19) Coulomb per electron. To determine the number of electrons passing through the heater, we use the definition of the current. We calculate as follows:

13.5 A = 13.5 C per second
Charge = 13.5 C/s (10 min) ( 60 s / 1 min)
Charge = 8100 C

Number of electrons = 8100 C / 1.602 x 10^(-19) C per electron
Number of electrons = 5.1 x 10^22 electrons

Therefore, there are 5.1 x10^22 electrons that assed through the heater for 10 minutes.

3 0

4 years ago

A tennis player hits a ball 2.0 m above the ground. The ball leaves his racquet with a speed of 20 m/s at an angle 5.0 ∘ above t

goldfiish [28.3K]

Answer:

Explanation:

initial height, yo = 2 m

initial velocity, u = 20 m/s

angle of projection,θ = 5 degree

distance of net = 7 m

height of net = 1 m

Let it covers a vertical distance y in time t .

Use Second equation of motion for vertical motion

$y=y_{0}+uSin\theta t-1/2 gt^{2}$

$y=2+20Sin5 t-4.9t^{2}$

As it hits the ground in time t, so put y = 0

$0=2+1.74 t-4.9t^{2}$

$4.9t^{2}-1.74t-2=0$

$t= \frac{1.74\pm\sqrt{1.74^{2}+4\times\2\times4.9}}{9.8}$

Taking positive sign, t = 0.84 s

The ball travels a horizontal distance x in time t

X = 20 Cos5 x t

X = 16.76 m

As this distance is more than the distance of net, so it clears the net.

Let t' be the time taken to travel a horizontal distance equal to the distance of net

7 = 20 cos5 x t'

t' = 0.35 s

Let the vertical distance traveled by the ball in time t' is y'.

So,

$y'=y_{0}+uSin\theta t'-1/2 gt'^{2}$

$y'=2+20Sin5 t-4.9\times0.35^{2}$

y' = 2.008 m

So, it clears the net which is 1 m high.

It clears the net by a vertical distance of 2.008 - 1 = 1.008 m and horizontal distance 16.76 - 7 = 9.76 m

3 0

3 years ago

You need to design a 60.0-Hz ac generator that has a maximum emf of 5200 V. The generator is to contain a 130-turn coil that has

dimaraw [331]

Answer:

B = 0.129 T

Explanation:

Given,

frequency, f = 60 Hz

maximum emf = 5200 V

Number of turns, N = 130

Area per turn = 0.82 m²

We know,

ω = 2 π f

ω = 2 π x 60 = 376.99 rad/s

now, Magnetic field calculation

$B =\dfrac{\epsilon_{max}}{NA\omega}$

$B =\dfrac{5200}{130\times 0.82\times 376.99}$

B = 0.129 T

Hence, the magnetic field is equal to B = 0.129 T

3 0

3 years ago

Can someone pls help, thank you in advance!

zzz [600]

Answer:

an object sliding down hill

Explanation:

On a slope, the force applied is due to gravity. Its direction is straight down. If the object is sliding down the hill, its displacement is at an angle to the applied force. The angle of displacement will depend on the steepness of the hill.

7 0

3 years ago