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2 years ago

(b) Can the speed of a rocket exceed the exhaust speed of the fuel? Explain.

Physics

1 answer:

muminat2 years ago

4 0

<u>Yes. The speed of a rocket can exceed the exhaust speed of the fuel.</u>

How this is explained?

The thrust of the rocket does not depend on the relative speed of the gases or the relative speed of the rocket.
It depends on conservation of momentum.

What is conservation of momentum?

Conservation of momentum, general law of physics according to which the quantity called momentum that characterizes motion never changes in an isolated collection of objects; that is, the total momentum of a system remains constant.

Momentum is equal to the mass of an object multiplied by its velocity and is equivalent to the force required to bring the object to a stop in a unit length of time.
For any array of several objects, the total momentum is the sum of the individual momenta.
There is a peculiarity, however, in that momentum is a vector, involving both the direction and the magnitude of motion, so that the momenta of objects going in opposite directions can cancel to yield an overall sum of zero.

To know more about conservation of momentum, refer:

brainly.com/question/7538238

#SPJ4

You might be interested in

What is the reversal experienced by an image formed in a plane mirror called?

algol [13]

Answer:

Lateral Inversion

Explanation:

lateral inversion simply means the change around of the image of an object from side to side

The image of an object formed by a plane mirror is laterally inverted.

5 0

3 years ago

True or false?

Ksju [112]

1. False

Explanation: it's exactly the opposite. In fact, Lenz's law states that the induced current and the induced emf in a conductor are generated in such a direction that opposes to the change in magnetic flux through the coil. This is summarized by the negative sign in the Faraday's Newmann Lenz law:

$\epsilon= -\frac{d\Phi }{dt}$

where $\epsilon$ is the emf induced and $\frac{d\Phi}{dt}$ is the rate of change of magnetic flux through the coil.

Lenz's law is a consequence of the law of conservation of energy. In fact, we have:

- If the magnetic flux through a coil is increasing, then the induced current has a direction such that the magnetic field generated by the coil is opposite to the direction of the external magnetic field, in order to decrease the total flux

- If the magnetic flux through a coil is decreasing, then the induced current has a direction such that the magnetic field generated by the coil is in the same direction as the external field, in order to increase the total flux

2. False

Explanation: the magnetic flux through a surface is given by

$\Phi = BA cos \theta$

where

B is the magnitude of the magnetic field

A is the surface area

$\theta$ is the angle between the direction of B and the normal vector to the surface

As we see, the magnetic flux depends not only on B and A, but also on the orientation of the coil with respect to the magnetic field.

3. False

Explanation:

- Sound waves are mechanical waves: mechanical waves are waves consisting of oscillations of the particles in a medium. Due to their nature, therefore, mechanical waves can propagate only in the presence of a medium

- Electromagnetic waves are NOT mechanical waves: they consist of oscillations of electric and magnetic fields, in a direction perpendicular to the direction of propagation of the wave. Since em waves are not mechanical waves, they do NOT need a medium to propagate, since they can also travel through a vacuum; therefore the original statement is false.

5 0

3 years ago

9. Two moving objects will change their motion if which of the following is true? a.There is no friction on the objects. b. The

adoni [48]

Answer:

lol

Explanation:

lolllll i need points sorry

8 0

3 years ago

What type of stars will potentially one day

xz_007 [3.2K]

Answer:

2, High mass stars.

Add-on:

i hope this helped at all. im sorry if its incorrect.

4 0

2 years ago

A car starting from rest accelerates uniformly at 4.3 m/s^2 for 5.0 seconds. How far does the car move?

andreev551 [17]

Answer:

Vf = 21.5 [m/s]

Explanation:

To solve this problem we must use the following kinematics equation:

$v_{f}= v_{i} +(a*t)\\$

where:

Vf = final velocity [m/s]

Vi = initial velocity = 0

a = aceleration = 4.3 [m/s^2]

t = time = 5 [s]

Now replacing:

Vf = 0 + (4.3*5)

Vf = 21.5 [m/s]

8 0

3 years ago