How long does gun residue last on hands?

in the 1950s an experimental train that had a mass of 33200kg was powered across a level track by a jet that produced a thrust o

Mashcka [7]

248482000 force*dist=work

4 0

3 years ago

George uses crayons to draw a model of the solar system on a sheet of paper. What is a limitation of this model? A. George canno

Yuliya22 [10]

D. The answer is D because any other scenario is possible. For example, in A, John could very easily put the planets in order. In problem B, he could draw some planets bigger than others. On C, he could color the planets on a different color. He can not hovever, move the planets

5 0

4 years ago

Read 2 more answers

Energy is conventionally measured in Calories as well as in joules. One Calorie in nutrition is one kilocalorie, defined as 1 kc

IgorC [24]

Answer:

The answers to the questions are;

a. The number of times the student run the flight of stairs to lose 1.00 kg of fat is 829.23 times.

b. The average power output, in watts and horsepower, as he runs up the stairs is 158.026 watts.

c. The act of climbing the stairs is not a practical way to lose weight has to lose 1 kg of fat, the student needs to workout for about 26.49 hrs or 1.104 days.

Explanation:

To solve the question, we write out the known variables as follows

1 g of fat = 9.00kcal

Number of steps the student climbs = 95 steps

Height of each step = 0.150 m

Time it takes for the student to reach the top of the stairs = 57.5 s.

Efficiency of human muscles = 20 %

Mass of student, m = 65 kg

a. From the question, the energy expended by the student in climbing the stairs is the "work done" by the student.

The "work done" is the height climbed resulting in the gaining of gravitational potential energy P. E..

That is work done, W, = P. E. = m·g·h

Where:

h = The total height climbed by the student

g = Acceleration due to gravity = 9.81 m/s²

Therefore;

h = Height of each step × Number of steps the student climbs =

= 0.150 m/(step) × 95 steps = 14.25 m

Therefore, P. E. = 65 kg × 9.81 m/s² × 14.25 m = 9086.5125 kg·m²/s²

= 9086.5125 J

We remember that the efficiency of the muscle is 20 %

The formula for efficiency is

Efficiency = $\frac{Ene rgy Out put}{Energ y In put} \times 100 %$

The work produced by the muscle = Energy Output = 9086.5125 J

Energy input is given by

$\frac{Out put} {Effici ency}$ = 9086.5125 J/ (0.2) = 45432.5625 J

= 45.432 kJ

From the question, 1 g of fat = 9.00 kcal and

1 kcal = 4186 J

Therefore 1 g of fat can release 9.00 kcal × 4186 J = 37674 J

Therefore 1 kg of fat = 1000 g = 1000 × 37674 J = 37674 kJ

To consume the energy in 1 kg of fat the student therefore will run up the foight of stairs $\frac{37674 kJ}{45.432 kJ}$ times to make up the 37674 kJ energy contained in 1 kg of fat

That is $\frac{37674 kJ}{45.432 kJ}$ = 829.23 times

b. Power is the rate of doing work

That is Power output = $\frac{ WorkO utput }{Time}$ = $\frac{9086.5125 J}{57.5 s}$ = 158.026 watts

c. No as the activity student will have to spend a total time of

829.23 × 57.5 s = 47680.67 s climbing up the stairs alone and

47680.67 s = ‪13.24 Hours climbing up of which if the time to climb down is the same s climbing up, then we ave total time = 2× ‪13.24 Hours

= 26.49 hrs = 1.104 days exercising which is not humanly possible.

3 0

3 years ago

Explain why energy is needed in active transport.

alexira [117]

Because if not it wouldn't be able to move for example if you don't eat to get the energy you need you would be weak and not be able to move as much and not be able to transport yourself to places :) hope this helps

8 0

4 years ago

A simple gaussmeter for measuring horizontal magnetic fields consists of a stiff 52 cm wire that hangs from a conducting pivot s

vivado [14]

Answer:

8.1345°

Explanation:

We apply $\sum F_x=0$ to the wire to obtain: