PHYSICS
HIGH SCHOOL

Answer:

When Emmett is lifting a box vertically, the forces that must be added to calculate the total force are: the gravitational force, tension force(the force exerted by Emmett to the box and the force exerted by the box to Emmett), and air resistance force.

Answer:

Answer:

the answer is actually D. and

Explanation:

hope this helps :)

COLLEGE

A kangaroo can jump over an object 2.46 m high. (a) Calculate its vertical speed (in m/s) when it leaves the ground. m/s

(b) How long (in s) is it in the air?

Answer:

a) 6.95 m/s

b) 1.42 seconds

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration due to gravity = 9.81 m/s²

a) The vertical speed when it leaves the ground. is 6.95 m/s

Time taken to reach the maximum height is 0.71 seconds

Time taken to reach the ground from the maximum height is 0.71 seconds

b) Time it stayed in the air is 0.71+0.71 = 1.42 seconds

HIGH SCHOOL

Floods, droughts, fires, and earthquakes are examples of _____.

Answer;

Natural disasters

Explanation;- Floods, droughts, fires, and earthquakes are examples of natural disasters.
- Natural disasters are events that occur as a result of natural processes of the earth and cause adverse effects. They include, floods, volcanic eruptions, tsunamis, tornadoes, and hurricanes among others.
- These events are extreme, sudden events caused by environmental factors that injure people and damage property. For example, floods and earthquakes may strike anywhere on earth , often without warning.

Floods, droughts, fires, and earthquakes are examples of ****natural disasters***

HIGH SCHOOL

A 32.5 g cube of aluminum initially at 45.8 °C is submerged into 105.3 g of water at 15.4 °C. What is the final temperature of both substances at thermal equilibrium? (Assume that the aluminum and the water are thermally isolated from everything else.)

Answer:

Explanation:

At thermal equilibrium we have heat given by aluminium must be equal to the heat absorbed by the water

so we will have

so we will have

so we have

so we have

MIDDLE SCHOOL

The gravitational strength on Earth is less than the gravitational strength on Neptune. Which statement is correct? a. The mass of an object will be greater on Earth than Neptune.

b. The mass of an object will be greater on Neptune than Earth.

c. The weight of an object will be greater on Earth than Neptune.

d. The weight of an object will be greater on Neptune than Earth.

The last choice (d) is the correct one.

By the universal law of newton we can say that the mass is directly proportional to the product of masses of that two object.

MIDDLE SCHOOL

A reef may lose its color due to...bleaching

A reef may lose its color due to CORAL bleaching

COLLEGE

How do astronomers use the Doppler effect to determine the velocities of astronomical objects?

Astronomers apply the Doppler effect because from there it is possible to obtain information about the change of light, which in turn affects the light spectrum and determines the movement of a body moving away or approaching us. The extent of the shift is directly proportional to the source's radial velocity relative to the observer.

The phenomenon that occurs to determine this process is linked to the wavelength. When the wave source moves towards you, the wavelength tends to decrease. This leads to a change in the color of the light moving towards the end of the spectrum, that is, towards the color blue. (It is really violet, but by convention the color blue was chosen as it is a more common color) When the source moves away from you and the wavelength lengthens, we call the color change a shift to red. Because the Doppler effect was first used with visible light in astronomy, the terms "blue shift" and "red shift" were well established.

COLLEGE

Consider a disk of radius 4.9 cm with a uni- formly distributed charge of +5.6 (C. Compute the magnitude of the electric field at a point on the axis and 3 mm from the center. The value of the Coulomb constant is 8.98774 x 10 N m2/C2

Answer:

Explanation:

Given that,

Radius of the disk, r = 4.9 cm = 0.049 m

Charge, q = +5.6 C

We need to find the the electric field at a point on the axis and 3 mm from the center, x = 0.003 m

At a point on the axis of a ring, the electric field is given by :

So, the electric field at a point on the axis is . Hence, this is the required solution.

HIGH SCHOOL

When the height of the cylinder increased by a factor of 5, from 100 m to 500 m, what happened to the cylinder’s gravitational potential energy?

It increased by a factor of 5

PE = m*g*h ⇒ 5* PE = 5*m*g*h

HIGH SCHOOL

Cameron and sabrina are the same weight and climb up the same flight of stairs. if Sabrina climbs faster then Cameron who had more Power?

If they have same weight and Sabrina climbs faster, then Sabrina has more power.