The first law of thermodynamics can be written as

where

is the variation of internal energy of the system

is the amount of heat absorbed by the system

is the work done by the system on the surrounding.
Using this form, the sign convention for Q and W becomes:
Q > 0 --> heat absorbed by the system (because it increases the internal energy)
Q < 0 --> heat released by the system (because it decreases the internal energy)
W > 0 --> work done by the system (for instance, an expansion: when the system expands, it does work on the surrounding, and so the internal energy decreases, this is why there is a negative sign in the formula Q-W)
W < 0 --> work done by the surrounding on the system (for instance, a compression: when the system is compressed, the surrounding is doing work on the system, and so the internal energy of the system increases)
Answer:0.27
Explanation:
Given
One worker Pushes with force 
other Pulls it with a rope of rope 
mass of crate 
both forces are horizontal and crate slides with a constant speed
Both forces are in the same direction so Friction will oppose the forces and will be equal in magnitude of sum of two forces because crate is moving with constant speed i.e. net force is zero on it

where
is the friction force



where
is the coefficient of static friction



Solution= The answer is true
(a) The momentum of the proton is determined as 5.17 x 10⁻¹⁸ kgm/s.
(b) The speed of the proton is determined as 3.1 x 10⁹ m/s.
<h3>
Momentum of the proton</h3>
The momentum of the proton is calculated as follows;
K.E = ¹/₂mv²
where;
- m is mass of proton = 1.67 x 10⁻²⁷ kg
- v is speed of the proton = ?
<h3>Speed of the proton</h3>
v² = 2K.E/m
v² = (2 x 50 x 10⁹ x 1.602 x 10⁻¹⁹ J)/(1.67 x 10⁻²⁷)
v² = 9.6 x 10¹⁸
v = 3.1 x 10⁹ m/s
<h3>Momentum of the proton</h3>
P = mv = (1.67 x10⁻²⁷ x 3.1 x 10⁹) = 5.17 x 10⁻¹⁸ kgm/s
Learn more about momentum here: brainly.com/question/7538238
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Answer:
The positive impact in the cycle is that CO2 will make plants to use water more efficiently and also thereby make them to become drought resistant and thereby grow faster.
Explanation:
Carbon cycle is the process by which carbon dioxide travels from the atmosphere to the earth and returns back to the atmosphere.
The negative impact of carbon dioxide in the carbon cycle is that it will cause green house effect. However, when it comes to the positive impact in the cycle, CO2 will make plants to use water more efficiently and also thereby make them to become drought resistant and thereby grow faster.