Homework help asap!!

ikadub [295]

Answer:

Explanation:

Law of conservation of momentum is applied in solving collision problem. When two body collides, their momentum after collision can be determined using the law.

The law States that the sum of momentum of two bodies before collision is equal to the sum of their momentum after collision. Before collision, both bodies moves with a different velocity while during some cases, the bodies moves with a common velocity after collision.

Whether they move with or without the same velocity depends on the type of collision that exists between them after the collision. After collision, some object sticks together and move with a common velocity while some doesn't.

If the bodies sticks together after collision, the type of collision that occur is inelastic (energy is not conserved) and if they splits after collision, the type of collision that occur is an elastic collision (energy is conserved).

Let m1 and m2 be the masses of the bodies

u1 and u2 be their velocities before collision

v1 and v2 be their velocities after collision.

According to the law;

m1u1 + m2u2 = m1v1 + m2v2

Note that momentum = mass × velocity of the body.

5 0

3 years ago

A rocket is moving with constant velocity of 2000ms and accelerates uniformly at 10ms. What is the velocity after 5 minutes?

AnnyKZ [126]

The velocity is 300ml in 5 mins

8 0

3 years ago

Determine the voltage ratings of the high-and-low voltage windings for this connection and the MVA rating of the autotransformer

SIZIF [17.4K]

Complete Question

The complete question is shown on the first uploaded image

Answer:

a

The High Voltage Rating for Auto - Transformer is 86kV

The Low Voltage Rating for Auto - Transformer is 78kV

The MVA rating is 268.75 $MVA$

b

The efficiency is 99.4%

Explanation:

From the question we are given are given that

The transformer has Mega Volt Amp rating of 25MVA

The frequency is 60-Hz

Voltage rating 8.0kV : 78kV

The short circuit test gives : 453kV,321A,77.5kW

The open circuit test gives : 8.0kV, 39.6A, 86.2kW

This can be represented on a diagram shown on the second uploaded image

From this diagram we can deduce that the The High Voltage Rating for Auto - Transformer is 86kV and the Low Voltage Rating for Auto - Transformer is 78kV

Now to obtain the current flowing through the 8kV coil in the Auto-transformer we have

$\frac{25 \ Mega \ Volt\ Ampere }{8\ Kilo Volt}$

The volt will cancel each other

$\frac{25*10^6}{8*10^3} = 3125\ A$

Now to obtain the required MVA rating we would multiply the value of Power obtained during the open circuit test by the value of the current calculated.we are making use of the power obtain during open circuit testing because the transformer at this point is not under any load.

$MVA \ rating = (86*10^3)(3125) =268.75$