All categories

3 years ago

An arrow of mass 0.5kg so it has 25J of kinetic energy; find the speed of the arrow v = m/s

Physics

1 answer:

miss Akunina [59]3 years ago

4 0

Answer:

10 m/s

Explanation:

Use the kinetic energy formula:

KE=(1/2)mv^2

I always remember it as Kevin is half-mad, and very square.

25J = (1/2)*0.5kg*(v^2)

50J = 0.5kg*(v^2)

100J = v^2

v = 10 m/s

Check it:

KE = (1/2)*0.5*(10^2)

KE = 25J

yep, it's right!

You might be interested in

A hamster eats a carrot before using its hamster wheel. The hamster wheel is connected to a generator which powers a light bulb.

Andrei [34K]

Answer: Chemical → Mechanical → Electrical → Radiant

Explanation:

First, the Hamster eats the carrot, then the hamster is getting chemical energy.

Now the hamster starts using his wheel, then he "transforms" the chemical energy into mechanical energy.

Now the mechanical energy is connected to a generator, this means that the mechanical energy (the rotation of the wheel) is being converted into electrical energy.

And we know that there is a light bulb powered by this electrical energy, then we have electrical energy being transformed into radiant energy.

Then the correct option is:

Chemical → Mechanical → Electrical → Radiant

6 0

3 years ago

A child pulls a sled up a snow covered hill. If the child does 504J of work on the sled while pulling the sled 23m up the hill t

zhenek [66]

Explanation:

ans is equal to 504j* 23 m* 10 ms

7 0

3 years ago

Please help me to do this problem

Novosadov [1.4K]

Answer:

we got time and velocity over time.

so the distance is again the area underneath the graph

for a triangle with known base and height it's

4*10 / 2

distance traveled is 20

deceleration occurs when velocity decreases. that happens from t=2 till t=4

in 2 time-units we loose 10 units of velocity, so we decelerate by 5 units per 1 time

a (from t=2 to t=4) = -5v/t

7 0

3 years ago

On Earth, friction can be _____ but not removed.

Whitepunk [10]

Answer:

reduced

Explanation:

The use of bearing surfaces that are themselves sacrificial, such as low shear materials, of which lead/copper journal bearings are an example

4 0

3 years ago

two ships leave a port at the same time. The first ship sails on a bearing of 40 degrees at 18 knots and the second at a bearing

Yuliya22 [10]

Answer:

The distance between the ships is 87.84 km.

Explanation:

Given that,

Angle of first ship= 40°

Speed of first ship = 18 knots

Angle of second ship= 130°

Speed of second ship = 26 knots

We need to calculate the resultant velocity

Using cosine rule

$v=\sqrt{v_{1}^2+v_{2}^2-2v_{1}v_{2}\cos\theta}$

Put the value into the formula

$v=\sqrt{18^2+26^2-2\times18\times26\times\cos90}$

$v=\sqrt{18^2+26^2}$

$v=\sqrt{324+676}$

$v=10\sqrt{10}$

We need to calculate the distance between the ships

$d =v\times t$

Put the value into the formula

$d=10\sqrt{10}\times1.5\times1.852$

$d=87.84\ km$

Hence, The distance between the ships is 87.84 km.

7 0

3 years ago

An arrow of mass 0.5kg so it has 25J of kinetic energy; find the speed of the arrow v = m/s​

An arrow of mass 0.5kg so it has 25J of kinetic energy; find the speed of the arrow v = m/s