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3 years ago

What is the potential energy of a 5kg rock that is 7m high on a hill

Physics

1 answer:

Goryan [66]3 years ago

4 0

Explanation:

Gravitational potential energy = mgh = (5)(9.81)(7) = 343.35J.

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We are going to focus on the gravitational force between Earth and our Moon. The Earth has a mass of about 6 x 10/24 kg and the

Basile [38]

Answer

Gravity is what holds us down on the earth's (or moon's) surface. If you were to weigh yourself on a scale on Earth and then on the moon, the weight read on the moon would be 1/6 your earth weight

7 0

2 years ago

A circular loop of wire with radius r=0.0250 m and resistance r=0.390 ohms is in a region of spatially uniform magnetic field. t

slavikrds [6]

Answer:

0.0133 A

Explanation:

The time at which B=1.33 T is given by

1.33 = 0.38*t^3

t = (1.33/0.38)^(1/3) = 1.52 s

Using Faraday's Law, we have

emf = - dΦ/dt = - A dB/dt = - A d/dt ( 0.380 t^3 )

Area A = pi * r² = 3.141 *(0.025 *0.025) = 0.00196 m²

emf = - A*(3*0.38)*t^2

thus, the emf at t=1.52 s is

emf = - 0.00196*(3*0.38)*(1.52)^2 = -0.0052 V

if the resistance is 0.390 ohms, then the current is given by

I = V/R = 0.0052/0.390 = 0.0133 A

3 0

3 years ago

You stand on a frictionless platform that is rotating with an angular speed of 5.1 rev/s. Your arms are outstretched, and you ho

timurjin [86]

Answer:

$\omega'=19.419\ rev.s^{-1}$

Explanation:

Given:

angular speed of rotation of friction-less platform, $\omega=5.1\ rev.s^{-1}$

moment of inertia with extended weight, $I=9.9\ kg.m^2$

moment of inertia with contracted weight, $I'=2.6\ kg.m^2$

<u>Now we use the law of conservation of angular momentum:</u>

$I.\omega=I'.\omega'$

$9.9\times 5.1=2.6\times \omega'$

$\omega'=19.419\ rev.s^{-1}$

The angular speed becomes faster as the mass is contracted radially near to the axis of rotation.

5 0

3 years ago

What form water has the greatest kinetic energy

Ray Of Light [21]

Answer:

Boiling water

Explanation:

Boiling water because it has the most rapid movement.

4 0

3 years ago

If the average speed of a person was 1.2 meters/second, does this mean that their speed was exactly 1.2 meters/second the whole

alexandr1967 [171]

Average speed is defined by the following formula

$v = \frac{D}{t}$

here

D = total distance that an object move from its initial position to final position

t = total time of the motion

so here we will say that there is no such relation between initial or final speed or we can say maximum or minimum speed of object with average speed of object.

We only need to find the total distance and total time of motion in order to find the average speed

here we can see many examples like let say an object moves with speed v1 for time t1 and then with speed v2 for time t2 then here average speed is given as

$d = v_1 t_1 + v_2t_2$

since we know that distance covered is product of speed and time

that's why we used above equation for finding total distance

now the average speed will be

$v_{avg} = \frac{v_1t_1 + v_2 t_2}{t_1 + t_2}$

so this is how we can find the average speed for above motion

so average speed is always between maximum and minimum speed any value in-between.

It is neither the maximum value nor it is minimum value

7 0

3 years ago