A rocket that has a mass of 4000 lbm travels at 27,000 ft/sec. What is most nearly its kinetic energy

dolphi86 [110]

In cosmology, a view that the universe is always expanding but maintaining a constant average density, with matter being continuously created to form new stars and galaxies at the same rate that old ones become unobservable as a consequence of their increasing distance and velocity of recession.

6 0

3 years ago

Read 2 more answers

A 160 g basketball has a 32.7 cm diameter and may be approximated as a thin spherical shell. Starting from rest, how long will i

mafiozo [28]

Answer:

t = 0.24 s

Explanation:

As seen in the attached diagram, we are going to use dynamics to resolve the problem, so we will be using the equations for the translation and the rotation dyamics:

Translation: ΣF = ma

Rotation: ΣM = Iα ; where α = angular acceleration

Because the angular acceleration is equal to the linear acceleration divided by the radius, the rotation equation also can be represented like:

ΣM = I(a/R)

Now we are going to resolve and combine these equations.

For translation: Fx - Ffr = ma

We know that Fx = mgSin27°, so we substitute:

(1) mgSin27° - Ffr = ma

For rotation: (Ffr)(R) = (2/3mR²)(a/R)

The radius cancel each other:

(2) Ffr = 2/3 ma

We substitute equation (2) in equation (1):

mgSin27° - 2/3 ma = ma

mgSin27° = ma + 2/3 ma

The mass gets cancelled:

gSin27° = 5/3 a

a = (3/5)(gSin27°)

a = (3/5)(9.8 m/s²(Sin27°))

a = 2.67 m/s²

If we assume that the acceleration is a constant we can use the next equation to find the velocity:

V = √2ad; where d = 0.327m

V = √2(2.67 m/s²)(0.327m)

V = 1.32 m/s

Because V = d/t

t = d/V

t = 0.327m/1.32 m/s

t = 0.24 s

7 0

3 years ago

One mole of a substance contains 6.02 × 1023 protons and an equal number of electrons. If the protons could somehow be separated

Aleksandr [31]

Explanation:

it is almost zero .this is because the distance and the electrostatic force are inversely proportional

8 0

2 years ago

what happens to the period of revolution for the planets as they move farther away in position from the sun

Marina CMI [18]

It increases. Mercury takes 88 days to orbit the sun once. The Earth takes a year. Pluto takes 248 years.

3 0

3 years ago

3. Write any two types of force.

Lerok [7]

Answer:

An <u>applied force</u> is a force that is applied to an object by a person or another object. If a person is pushing a desk across the room, then there is an applied force acting upon the object. The applied force is the force exerted on the desk by the person.

A <u>friction force</u> is the force exerted by a surface as an object moves across it or makes an effort to move across it. There are at least two types of friction force - sliding and static friction. Though it is not always the case, the friction force often opposes the motion of an object. For example, if a book slides across the surface of a desk, then the desk exerts a friction force in the opposite direction of its motion. Friction results from the two surfaces being pressed together closely, causing intermolecular attractive forces between molecules of different surfaces. As such, friction depends upon the nature of the two surfaces and upon the degree to which they are pressed together. The maximum amount of friction force that a surface can exert upon an object can be calculated using the formula below:

$F_{frict}$ = µ • $F_{norm}$

8 0

3 years ago