PHYSICS
MIDDLE SCHOOL

Answer:

if an object is thrown upwards and then it will return back into our hand then we can say for the complete motion the displacement of the object must be zero

so here we will have

here we know that

now we will have this time t = 3 s on the surface of earth

again same experiment is performed on surface of moon with same initial speed

so the time on the surface of moon will be

so here we have

so it will take 18 s on moon

COLLEGE

How much heat must be added to 4.55 kg of copper to change it from a solid at 1358 K to a liquid at 1358 K? Latent heat of fusion for copper is Lf=20.7×104J/kg.

Answer:

H=9.42 X 10^5 J

Explanation:

Heat required H = Mass of copper x latent heat of fusion of copper

H=4.55 x 20.7×104

H=941850

H=9.42 X 10^5 J

HIGH SCHOOL

The coordinates of a bird flying in the xy-plane are given by x(t)=αt and y(t)=3.0m−βt2, where α=2.4m/s and β=1.2m/s2.part a:Calculate the velocity vector of the bird as a function of time. Give your answer as a pair of components separated by a comma. For example, if you think the xcomponent is 3 and the y component is 4, then you should enter 3,4. part b:Calculate the acceleration vector of the bird as a function of time. Give your answer as a pair of components separated by a comma. For example, if you think the x component is 3 and the y component is 4, then you should enter 3,4

Α

β

β

α

β

αβ

β

β

β

β

α

β

αβ

β

β

COLLEGE

The index of refraction for red light in a certain liquid is 1.303; the index of refraction for violet light in the same liquid is 1.326. part a find the dispersion θv−θr for red and violet light when both are incident on the flat surface of the liquid at an angle of 45.00 ∘ to the normal.

Snell's law states: n1/n2 = Sin Ф2/Sin Ф1

But n2/n1 = 1.303 and 1.326 for red light and violet light respectively (for this case) and Ф1 = 45

Therefore,

Фr = Sin ^-1{1/1.303 *Sin 45} = 32.87°

Фv = Sin ^-1 {1/1.326* Sin 45} = 32.23°

Then,

Dispersion, Фv - Фr = 32.23 - 32.87 = -0.64°

But n2/n1 = 1.303 and 1.326 for red light and violet light respectively (for this case) and Ф1 = 45

Therefore,

Фr = Sin ^-1{1/1.303 *Sin 45} = 32.87°

Фv = Sin ^-1 {1/1.326* Sin 45} = 32.23°

Then,

Dispersion, Фv - Фr = 32.23 - 32.87 = -0.64°

HIGH SCHOOL

Zebras are classified as vertebrates because they have two germ layers. bilateral symmetry. a backbone. a brain.

Because they Have A Backbone

HIGH SCHOOL

A statement that the energy supplied to a system in the form of heat, minus the work done by the system, is equal to the change in internal energy represents the ___________

Answer:

First law of thermodynamics.

Explanation:

The first law of thermodynamics states that the change in internal energy of a system ΔE equals to the amount of heat energy supplied to the system H , minus the work done by the system on its surroundings. W.

The above definition can be expressed mathematically as: ΔE = H - W

This can also be restarted as energy of a close or isolated system is constant.

HIGH SCHOOL

When the archer releases the arrow, the____energy in the bow string transforms into_____ energy for the arrow. *Drop box option 1* Motion Energy, Gravitational Potential Energy, Elastic Potential Energy

*Drop box option 2* Motion Energy, Gravitational Potential Energy, Elastic Potential Energy

Explanation :

When the archer releases the arrow, the elastic potential energy in the bowstring transforms into kinetic energy for the arrow.

The energy stored due to the deformation of an elastic object is called it is Elastic potential energy. Then the stored elastic potential energy gets converts to the motion energy.

Motion energy is related to the kinetic energy of the object.

Hence, the correct option is (1) Elastic Potential Energy and (2) Motion Energy.

Answer:

When the archer releases the arrow, the

elastic potential energy

energy in the bow string transforms into

motion energy

energy for the arrow.

Explanation:

MIDDLE SCHOOL

There is no air in space astronauts in space cannot hear sounds from outside their spacesuits explain this

In space, where there is no air, sound has no way to travel.

HIGH SCHOOL

Suppose you had used a less sensitive balance for the Archimedes method of getting volume of an object based on the difference in mass in water and out of water. Would that change the precisions of your density for that method?. They define sensitivity as the scale to which things are measured and precision as how repeatable something is.

There will be no change in the sensitivity of the method.

Information regarding the sensitivity is as follows:

- A less sensitive measuring method should be recorded the less errors of measurement.
- The sensitivity of a determining the device based on the error of measurement that it can accommodate.
- So here we can say that the more sensitive an instrument is, the more accurate it is.

Find out more information about the sensitivity here: brainly.com/question/1178549?referrer=searchResults

Answer:

There will be no change in the sensitivity of the method.

Explanation:

A less sensitive measuring method is less likely to record the small errors of measurement. The sensitivity of a measuring device depends on the error of measurement that it can accommodate. For example, is the length of a pen was to be measured by the ruler and a vernier caliper, the two measurements would be different. This is because the ruler would give a measurement to the nearest centimeter. However, the vernier caliper would provide a measurement to the nearest 0.1 cm which improves the accuracy and sensitivity of the measurement as well. Thus, the more sensitive an instrument is, the more accurate it is.

COLLEGE

An electron enters a region of uniform electric field with an initial velocity of 50 km/s in the same direction as the electric field, which has magnitude E = 50 N/C, (a) what is the speed of the electron 1.5 ns after entering this region? (b) How far does the electron travel during the 1.5 ns interval?

Answer:

(a). The speed of the electron is

(b). The distance traveled by the electron is

Explanation:

Given that,

Initial velocity = 50 km/s

Electric field = 50 N/C

Time = 1.5 ns

(a). We need to calculate the speed of the electron 1.5 n s after entering this region

Using newton's second law

.....(I)

Using formula of electric force

.....(II)

from equation (I) and (II)

(a). We need to calculate the speed of the electron

Using equation of motion

Put the value of a in the equation of motion

(b). We need to calculate the distance traveled by the electron

Using formula of distance

Put the value in the equation

Hence, (a). The speed of the electron is

(b). The distance traveled by the electron is