Physics, 07.01.2020 01:31 elyssa34972

A3.18-kg rock is released from rest at a height of 26.6 m. ignore air resistance and determine (a) the kinetic energy at 26.6 m, (b) the gravitational potential energy at 26.6 m, (c) the total mechanical energy at 26.6 m, (d) the kinetic energy at 0 m, (e) the gravitational potential energy at 0 m, and (f) the total mechanical energy at 0

Answers: 2

Show answers

Answers

Answer from: gabriel5575

(a) 0 J

(b) 828.96 J

(d) 828.96 J

(e) 0 J

(f) 828.96 J

Explanation:

Given:

Mass of the rock is, $m=3.18\ kg$

Initial height of the rock is, $h_{i}=26.6\ m$

Final height of the rock is, $h_f=0\ m$

Initial velocity of the rock is, $v_i=0\ m/s(Rest)$

Acceleration due to gravity is, $g=9.8\ m/s^2$

(a)

Initial kinetic energy is given as:

$K_i=\frac{1}{2}mv_i^2$

Plug in the given values and solve for ' K_i '. This gives,

$K_i=\frac{1}{2}\times 3.18\times 0^2=0$

Therefore, initial kinetic energy is 0 J.

(b)

Initial potential energy is given as:

$U_i=mgh_i\\U_i=3.18\times 9.8\times 26.6=828.96\ J$

Therefore, initial potential energy is 828.96 J.

(c)

Mechanical energy is equal to the sum of kinetic and potential energy. It is always a constant value. Therefore,

$ME=K_i+P_i\\ME=0+828.96=828.96\ J$

Therefore, mechanical energy at 26.6 m is 828.96 J.

(d)

Now, at the final height of 0 m, the decrease in potential energy will be equal to the increase in the kinetic energy. In other words, the potential energy at the start will be converted to kinetic energy at the bottom.

Therefore, kinetic energy at the 0 m is given as:

$K_f=U_i=828.96\ J$

(e)

Potential energy at the final height is given as:

$P_f=mgh_f=3.18\times 9.8\times 0=0\ J$

Therefore, final potential energy is 0 J.

(f)

Total mechanical energy is a constant and doesn't depend on the height.

So, total mechanical energy at 0 m is same as that at 26.6 m.

Total mechanical energy is 828.96 J.

Answer from: Quest

Velocity=total displacement/timefrom house to store is 500 from store to neighbor is 200 therefore total displacement=500+200=700metrestherefore,700metres/910seconds=0.8metres per second

Answer from: Quest

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current

Another question on Physics

Physics, 21.06.2019 20:20

Two friends are having a conversation. anna says a satellite in orbit is in freefall because the satellite keeps falling toward earth. tom says a satellite in orbit is not in freefall because the acceleration due to gravity is not 9.80 m/2 . who do you agree with and why?

Answers: 1

Answer

Physics, 22.06.2019 22:00

Ne way in which elements differ from each other is the structure of the electron cloud in each element's atoms. in an electron cloud, an electron that is farther away from the nucleus has

Answers: 1

Answer

Physics, 23.06.2019 04:31

You have 80 g of 60oc water and 80 g or 10oc water. what is the final temperature when the two are mixed? explain.

Answers: 2

Answer

Physics, 23.06.2019 10:30

How long will a plane have to fly continuously with 1100 miles per hour in order to cover the same distance as that from earth to the next star, proxima centauri?

Answers: 2

Answer

You know the right answer?

A3.18-kg rock is released from rest at a height of 26.6 m. ignore air resistance and determine (a) t...

Questions