What are physical forms in which a substance can exist?

A carnot engine operates between two heat reservoirs at temperatures th and tc. an inventor proposes to increase the efficiency

Sonja [21]

The efficiency of the first Carnot engine is
n1 = 1 - Th/T
The efficiency of the second Carnot engine is
n2 = 1 - T/Tc
The total efficiency of the engines put in series is
n = 1 - Th/Tc

5 0

2 years ago

In a pith ball experiment, the two pith balls are at rest. The magnitude of the tension in each string is |T|=0.55N, and the ang

Len [333]

Answer:

Explanation: Two pith ball will repel each other . they will remain balaced due to tension in the spring whose one component balances the weight and the other balances the repulsive force on each.

The gravitational force will be balanced by T cos 27.33 and the electrostatic repulsive force will be balanced by T sin27.33

So

Fg =T cos 27.33

= .55 X .888

= .49 N

Fq = T sin27.33

=.55 x .459

= .25 N.

5 0

1 year ago

A rigid, uniform bar with mass mmm and length bbb rotates about the axis passing through the midpoint of the bar perpendicular t

Pie

Answer:

$I = \frac{mvb}{6}$

Explanation:

we know angular velocity in terms of moment of inertia and angular speed

$L = I$ ω .... (1)

moment of inertia of rod rotating about its center of length b

$I = \frac{ mb^2}{12}$ ........ .(2)

using v = ωr

where w is angular velocity

and r is radius of rod which is equal to b

so we get 2v = ωb

ω = 2v/b ................. (3)

here velocity is two time because two opposite ends are moving opposite with a velocity v so net velocity will be 2v

put second and third equation in ist equation

$L = \frac{mb^2}{12}$ × $\frac{2v}{b}$

so final answer will be $L = \frac{mvb}{6}$

7 0

2 years ago

In this lab you will use a cart and a track to explore Newton's second law of motion. You will vary two different variables and

Savatey [412]

Answer:

Newtons II law:

It is defined as "the net force acting on the object is a product of mass and acceleration of the body" . Also it defines that the "acceleration of an object is dependent on net force and mass of the body".

Let us assume that,a string is attached to the cart, which passes over a pulley along the track. At another end of the string a weight is attached which hangs over the pulley. The hanging weight provides tension in the spring, and it helps in accelerating the cart. We assume that the string is massless and no friction between pulley and the string.

Whenever the hanging weight moves downwards, the cart will accelerate to right side.

For the hanging weight/mass

When hanging weight of mass is m₁ and accelerate due to gravitational force g.

Therefore we can write F = m₁ .g

and the tension acts in upward direction T (negetive)

Now, Fnet = m₁ .g - T

= m₁.a

So From Newtons II law F = m.a

3 0

1 year ago

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This is a cell, which is the basic unit of all life. All organs in human bodies are made of cells and require oxygen to survive.

kotegsom [21]

The two systems that work together to deliver oxygen are D, respiratory and cardiovascular

5 0

1 year ago