The SI unit for energy is Newton true or false

A steam engine absorbs 1.98 × 105 j and expels 1.49 × 105 j in each cycle. assume that all of the remaining energy is used to do

VikaD [51]

B) The heat absorbed by the engine is $Q_{in} = 1.98 \cdot 10^5 J$ while the heat expelled is $Q_{out} = 1.49 \cdot 10^5 J$ , therefore the work done by the engine is the difference between the heat absorbed and the heat expelled:
$W=Q_{in} - Q_{out} = 1.98 \cdot 10^5 J - 1.49 \cdot 10^5 J = 0.49 \cdot 10^5 J$

a) The efficiency of the engine is the ratio between the work done by the engine and the heat absorbed, therefore:
$\eta= \frac{W}{Q_{in}} = \frac{0.49 \cdot 10^5 J}{1.98 \cdot 10^5 J}=0.247 = 24.7\%$

8 0

4 years ago

I neeed help im so comfused Points Possible: 1, Points Correct: 0 Which group of numbers is listed from greatest to least? -3, -

Alona [7]

The groups aren't well formatted ;

The groups are ;

(-3, -1, 0, 2, 7) ; (9, 7, 6, -5, -4) ; (8, -6, 5, -4, 1) ; (-3, -4, -7, -8, -9)

Answer:

(-3, -4, -7, -8, -9)

Explanation:

Given the following group of numbers :

Evaluating each group of values for which is correctly arranged from greatest to least.

(-3, -1, 0, 2, 7) : - 1 is greater than - 3 (the group isn't arranged from greatest to least)

(9, 7, 6, -5, -4) : - 4 is greater than - 5 ; hence, the group isn't arranged from greatest to least

(8, -6, 5, -4, 1) : 5 is greater than - 6 ; hence, the group isn't arranged from greatest to least

(-3, -4, -7, -8, -9) ; the group of numbers here is arranged from greatest to least ;

(-3 > -4 > -7 > -8 > -9) ; hence, the correct group

5 0

3 years ago

Annie has a soccer ball and a cake ball she kicks each ball with the same Force the soccer ball accelerates at 3 m per second sq

lana [24]

Answer: The acceleration will be greater in the kickball than the soccer ball since the kick ball has a smaller mass and provided they are acted upon with equal force magnitude.

Explanation:

We can prove this by substituting with numerical values.

Say the force she kicked both balls with was 30 N. The mass of the soccer ball is 10kg and the mass of the kickball is 6kg.

Applying Newtons Second Law, F = ma

For the soccer ball:

30 = 10a
a = 30/10
a = 3

For the kickball:

30 = 6a
a = 30/6
a = 5

Hence the kickball will travel with a greater acceleration given the same force is acted upon and has a smaller mass than the soccer ball

Hope this helps, brainliest would be appreciated :)

4 0

3 years ago

Which of the following is NOT a vector quantity?

lora16 [44]

Answer:

D

Explanation:

Acceleration has both magnitude and direction. because velocity is vector quantity

average velocity is vector

linear momentum = mass× velocity

therefore it's also vector

force = mass× acceleration

acceleration is vector therefore force also vector

potential energy= mgh

energy in any form is scaler quantity therefore potential energy too is a scaler quantity.

5 0

3 years ago

A. Protons and neutrons make up the nucleus of an atom. Write 3 - 4 sentences describing the electrostatic force between each pa

Vladimir [108]

a) Proton-proton: high repulsive electrostatic, very high attractive nuclear force. Proton-neutron: no electrostatic forces since neutrons are not charge carriers, high attractive nuclear force. Neutron-neutron: no electrostatic force for the same reason and huge attractive nuclear force.

b) There are two types of forces in the nuclei: repulsive electrostatic and attractive nuclear. Nuclear act between all nucleons, electrostatic only between protons. To make a nucleus stronger, increase number of attractive forces by increasing amount of neutrons.

c) Cause due to equivalence between mass and energy E=mc^2 change in energy (which happens in nuclear reaction) causes on change in mass. Starting mass just converts to energy, that's why it's greater than the ending mass.

7 0

4 years ago

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