All categories

3 years ago

How much work does a 65 kg person climbing a 2000 m high cliff do?

Physics

1 answer:

qaws [65]3 years ago

3 0

The answer for the following question is explained below.

Therefore the work done is 130 kilo Joules.

Explanation:

Work:

A force causing the movement or displacement of an object.

Given:

mass of the person (m) = 65 kg

height of the cliff (h) = 2000 m

To calculate:

work done (W)

We know;

According to the formula:

W = m × g × h

Where;

m represents mass of the person

g represents the acceleration due to gravity

where the value of g is;

g = 10 m/ s²

h represents the height of the cliff

From the above formula;

W = 65 × 10 × 2000

W = 130,000 J

W = 130 Kilo Joules

Therefore the work done is 130 kilo Joules.

You might be interested in

A car initially at rest accelerates at 10m/s^2. The car’s speed after it has traveled 25 meters is most nearly... A.) 0.0m/s B.)

STALIN [3.7K]

The car traverses a distance $x$ after time $t$ according to

$x=\dfrac12at^2$

where $a$ is its acceleration, 10 m/s^2. The time it takes for the car to travel 25 m is

$25\,\mathrm m=\left(5\dfrac{\rm m}{\mathrm s^2}\right)t^2\implies t=\sqrt 5\,\mathrm s$

5 is pretty close to 4, so we can approximate the square root of 5 by 2. Then the car's velocity $v$ after 2 s of travel is given by

$v=\left(10\dfrac{\rm m}{\mathrm s^2}\right)(2\,\mathrm s)\approx20\dfrac{\rm m}{\rm s}$

which makes C the most likely answer.

3 0

3 years ago

Rebecca heated 50mL of water from 0 degrees Celsius to 60 degrees Celsius. How much energy did she use to heat the water? Rememb

GuDViN [60]

Answer:

Q = 12540 J

Explanation:

It is given that,

Mass of water, m = 50 mL = 50 g

It is heated from 0 degrees Celsius to 60 degrees Celsius.

We need to find the energy required to heat the water. The formula use to find it as follows :

$Q=mc\Delta T$

Where c is the specific heat of water, c = 4.18 J/g°C

Put all the values,

$Q=50\times 4.18\times (60-0)\\Q=12540\ J$

So, 12540 J of energy is used to heat the water.

7 0

2 years ago

If the mass of both objects are doubled while the

lutik1710 [3]

Answer:

The force becomes 16 times what it is now.

Explanation:

The formula for gravitational force is

F = G * m1 * m2 / r^2

When you do what you have described, you are setting a stage that not even the USS Enterprise (Star Trek) can get out of. The increase is huge.

If you double m1 and m2 and don't do anything to r, you've already increased the force by 4 times. (2m1 * 2m2 = 4 * m1 * m2)

But you are not finished. If you 1/2 the distance, you are again increasing the Force by 4 times. 1 / (2r) ^2 = 1/ 4* r^2

Because this is in the denominator, the 1/4 is going to flip to the numerator.

So the total increase is going to be 4 * (4 * m1 * m2) = 16 * m1 * m2.

Think about what that means. If you were out golfing, your drives would be roughly 1/16 times as far as they are now. Also you would be lugging around 16 times your weight around the golf course. My feeling is that you would never finish 5 holes at that rate.

3 0

2 years ago

The maximum wavelength that an electromagnetic wave can have and still eject electrons from a metal surface is 542 nm. What is t

Veseljchak [2.6K]

Answer:

2.295 eV

Explanation:

maximum wavelength, λ = 542 nm = 542 x 10^-9 m

The work function of the metal is defined as the minimum amount of energy falling on the metal so that the photo electrons just ejects the surface of metal.

$W_{o}=\frac{hc}{\lambda }$