Answer:
A:- 50 J
B:- 500 J
Explanation:
a) Given that a 25 N force is applied to move the box. Also the floor is having friction surface.
So in order to move the box, the floor should have friction of atleast 25 N.
∴ friction = 25 N
Work done = force * displacement of box
Given, the box is moved 2 m across the floor
So, Work done = friction * 2 m
= 25 * 2
= 50 J
b) Given, the box is having weight of 250 N weight
Gravitational force is acting on the box which is equal to (mass * gravity)
∴ Force = 250 N
The box is lifted 2 m above the floor.
So, displacement = 2 m
Work done = force * displacement of box
Work done = 250 * 2
= 500 J
Answer:
The risks and expense of manned deep water exploration must be balanced with the knowledge that will be gained.
Explanation:
Storage form of energy:
- Potential energy
- Nuclear energy
- electrical energy
- thermal energy
- magnetic energy
Potential energy:
All stationary objects are having potential energy stored in it. This energy can be transferred in form of kinetic energy when it comes in the motion from rest. Example, An object placed at height h having potential energy in it. When it comes in motion from the rest the potential energy is converted into kinetic energy.
Nuclear energy:
Nuclear energy is energy that is stored in nucleus of any element. Example, fusion reaction on sun gives earth solar energy.
Electric energy:
Electrical energy is due to movement of the electrical charges. Example, In elctrical batteries electrical energy is stored.
Thermal energy:
Thermal energy is the internal energy of a substance that is transferred to other substance in the form of heat. Example, on heating water is a beaker stem energy is developed.
Magnetic energy:
Magnetic energy is the potential energy stored in the magnetic field. Example, using magnetic energy electric field is produced according to Faraday's law.
Answer:
Global warming pollution
When we burn oil, coal, and gas, we don't just meet our energy needs—we drive the current global warming crisis as well. Fossil fuels produce large quantities of carbon dioxide when burned. Carbon emissions trap heat in the atmosphere and lead to climate change
Explanation:
Answer:
D. 66.4
Explanation:
So this problem uses SOHCAHTOA or the three trig functions.
Specifically this uses cosine, because it has an adjacent and a hypotenuse.
First you would determine what to do on the calculator, and since the problem is saying so, use the inverse cosine button. This will give you a angle measure from the decimal.
On a calculator, type in cos^-1(6/15). I used 6/15 because cosine is adjacent over hypotenuse. This will give you 66.4, which is D on the answers.
