The method of heat transfer by which the sun warms the earth is

A gas is compressed at a constant pressure of 0.800 atm from 12.00 L to 3.00 L. In the process, 390 J of energy leaves the gas b

Andru [333]

Answer:

a)W= - 720 J

b)ΔU= 330 J

Explanation:

Given that

P = 0.8 atm

We know that 1 atm = 100 KPa

P = 80 KPa

V₁ = 12 L = 0.012 m³ ( 1000 L = 1 m³)

V₂ = 3 L = 0.003 m³

Q= - 390 J ( heat is leaving from the system )

We know that work done by gas given as

W = P (V₂ -V₁ )

W= 80 x ( 0.003 - 0.012 ) KJ

W= - 0.72 KJ

W= - 720 J ( Negative sign indicates work done on the gas)

From first law of thermodynamics

Q = W + ΔU

ΔU=Change in the internal energy

Now by putting the values

- 390 = - 720 + ΔU

ΔU= 720 - 390 J

ΔU= 330 J

5 0

3 years ago

iron ball weight 400 gram inside water when it is completely impressed in water 53 gram water is displaced what will be the weig

Alika [10]

Answer:

453 gm

Explanation:

<u>Immersed </u>objects are buoyed up by force equal to mass of displaced liquid

400 + 53 = 453 gm in air

8 0

2 years ago

One knife is longer from the cutting edge to the back of the blade. It's easier to push the longer knife through a pear and more

AlladinOne [14]

By the formula of torque balance we know that

$\tau = r\times F$

here we know that

r = distance of force

F = applied force

so here we know that as we will take large edge knife then the distance of force will increase

due to this the torque will also increase in it so it is easy to pear it

So here we can say

$F_{in}r_1 = F_{out}r_2$

$F_{out} = \frac{r_1}{r_2} F_{in}$

so output force will increase in this case

So here the correct answer would be

<em>b. the longer the knife, the stronger the output force</em>

6 0

3 years ago

____________ was a series of human spaceflight missions undertaken by the u.S. Devoted to the goal of landing a man on the moon

4vir4ik [10]

Answer:

The Apollo program or Project Apollo was a series of human spaceflight missions undertaken by the u.S. Devoted to the goal of landing a man on the moon and returning him to earth safely.

Explanation:

Project Apollo or Apollo program was the spaceflight program carried out by the United States of America during the years 1961-1972 using the Apollo spacecraft. This project's main goal was to land a man on the Moon and to safely return him to Earth. This goal was accomplished with the Apollo 11 moon-landing mission on July 20, 1969, when an Apollo Lunar Module (LM) landed on the Moon's surface and the astronauts Neil Armstrong and Buzz Aldrin walked on the lunar surface while Michael Collins stayed in the command and service module (CSM) in the lunar orbit. On July 24, all three astronauts landed safely on Earth.

This project included three unmanned test flights (Apollo 4 through Apollo 6) and eleven manned flights (Apollo 7 through Apollo 17). All these spaceflight missions were carried out by NASA (National Aeronautics and Space Administration) and all were launched from the Kennedy Space Center, Florida.

7 0

3 years ago

Two ice skaters, Paula and Ricardo, initially at rest, push off from each other. Ricardo weighs more than Paula.

sveta [45]

Answer:

the two ice skater have the same momentum but the are in different directions.

Paula will have a greater speed than Ricardo after the push-off.

Explanation:

Given that:

Two ice skaters, Paula and Ricardo, initially at rest, push off from each other. Ricardo weighs more than Paula.

A. Which skater, if either, has the greater momentum after the push-off? Explain.

The law of conservation of can be applied here in order to determine the skater that possess a greater momentum after the push -off

The law of conservation of momentum states that the total momentum of two or more objects acting upon one another will not change, provided there are no external forces acting on them.

So if two objects in motion collide, their total momentum before the collision will be the same as the total momentum after the collision.

Momentum is the product of mass and velocity.

SO, from the information given:

Let represent the mass of Paula with $m_{Pa}$ and its initial velocity with $u_{Pa}$