1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
kozerog [31]
3 years ago
8

A ladder is balanced against a wall without moving. What must be true about this ladder?

Physics
1 answer:
Mandarinka [93]3 years ago
6 0

Answer:a no net force

Explanation: google lol

You might be interested in
Energy is conventionally measured in Calories as well as in joules. One Calorie in nutrition is one kilocalorie, defined as 1 kc
Sergeeva-Olga [200]

Answer:

a) The student must run flight of stairs to lose 1.00 kg of fat 709.5 times.

b) Average power

P(w)= 1062.07 [w]

P(hp)=1.42 [hp]

c) This activity is highly unpractical, because the high amount of repetitions he has to due in order to lose, just 1 Kg of fat.

Explanation:

First, lets consider the required amount of work to move the mass of the student. (considering running stairs just as a vertical movement)

Work:

W= F*d= m*g*d

Where m is the mass of the student, g is gravity (9.8 m/s) and d is the total distance going up the stairs (0.15m *85steps= 12.75m )

W= F*d= m*g*d=85* 9.8*12.75=10620.75 [J]

Converting from Joules to Kcals:

\frac{10620.75}{4186} =2.537 Kcal

Now lets take into account the efficiency of the human body (20%)

2.537 ---> 20%

 x       ---> 100%

x=\frac{2.537*100}{20} =12.685

So the student is consuming 12.685 KCals each time he runs up the stairs.

Now,

1 g --> 9 Kcals

1000 g --> 9000KCals

Burning 1 g of fat, requieres 9 KCals, 1000g burns 9000KCals. So in order to burn a 1Kg of fat:

\frac{9000Kcals}{12.685Kcals} =709.5 times

He must run up the stairs 709.5 times, to burn 1 Kg of fat.

********************

For b) just converting units, taking into account the time lapse. (53103.75 is the 100% of the energy in joules, from converting 12.685Kcals to joules)

Power=\frac{Joules}{Seconds} =\frac{53103.75}{50} =1062.075 [W]\\

P(hp)=\frac{P(w)}{745.7} =\frac{1062.075}{745.7} =1.42[hp]

*****

4 0
3 years ago
A material that does not conduct electricity is called a... what?
xxTIMURxx [149]

A material that does not conduct electricity is known as an insulator

3 0
3 years ago
The energy due to Earth pulling down on an object is called ___.
Slav-nsk [51]

Gravity is the energy due to Earth pulling down on an object.

6 0
3 years ago
A spacecraft and a staellite are at diametrically opposite position in the same circular orbit of altitude 500 km above the eart
Tanya [424]

Answer:

Hello the diagram related to your question is attached below

answer: a) 851 m/s

             b)  8506.1 secs

Explanation:

calculate the periodic time of the satellite using the equation below

t = \frac{2\pi }{R} \sqrt{\frac{(R+h)^{3} }{g} }  --  ( 1 )

where ; R = 6370 km

h = 500 km

g = 9.81 m/s^2

input given values into equation 1

t = 5670.75 secs

next calculate the periodic time taken by the space craft  

<u>a) determine the increase in speed </u>

V = v - \sqrt{\frac{gR^2}{R + h} }  

where ; v = 8463 m/s , R = 6370 km, h = 500 km

V = 851 m/s

b) Determine the periodic time for the elliptic orbit

τ = \frac{3t}{2}

 = \frac{3*5670.76}{2}  =  8506.1 secs

attached below is the remaining part of the detailed solution

5 0
3 years ago
How is the temperature of an object related to the average kinetic energy of its particle??
dusya [7]
By <span> It is directly proportional to the </span>average kinetic energy<span>.</span>
6 0
3 years ago
Read 2 more answers
Other questions:
  • You could use an elevator or the stairs to lift a box to the tenth floor.which has greater power?why?
    11·2 answers
  • Is this the actual answer??
    7·1 answer
  • Mr. Phillips' car iso parked on a steep hill
    6·1 answer
  • Maximum voltage produced in an AC generator completing 60 cycles in 30 sec is 250V. (a) What is period of armature? (b) How many
    6·1 answer
  • We divide the electromagnetic spectrum into six major categories of light, listed below. Rank these forms of light from left to
    7·1 answer
  • A toroidal solenoid has an inner radius of 12.0 cm and an outer radius of 15.0 cm . It carries a current of 1.50 A . Part A How
    15·1 answer
  • What is the correct answer?
    5·2 answers
  • 3. Light travels from the Sun to Earth in 8.3 min. Given that the speed of light is 3.00108 m/s, what is the distance in meters
    10·1 answer
  • A person kicks a rock off a cliff horizontally with a speed of 20 m/s. It takes 7.0 seconds to hit the ground.
    9·1 answer
  • HELP
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!