The magnitude of work done by the gas is 279 J and the sign is negative so W = -279 J as work is done by the system.
<u>Explanation:</u>
According to first law of thermodynamics, the change in internal energy of the system is equal to the sum of the heat energy added or released from the system with the work done on or by the system. If the heat energy is added to the system to perform a certain work, then the heat energy is taken as positive, while it will be negative when the heat energy is released from the system.
Similarly, in this case, the heat energy of 597 J is added to the system. So the heat energy will be positive, while the gas expansion occurs means work is done by the system.
ΔU = Q+W
Since ΔU is the change in internal energy which is given as 318 J and the heat energy added to the system is Q = 597 J.
Then the work done by the gas = ΔU - Q = 318 J - 597 J = - 279 J.
As the work is done by the system, so it will be denoted in negative sign and the magnitude of work done by the gas is 279 J.
Answer:
Newton's third law of motion.
Explanation:
An ice skater at rest pushes against a sled at rest,causing both the skater and sled to move away from each other with different acceleration. It is based on Newton's third law of motion.
Third law says that, for every action there is an equal; and opposite reaction. Here, action is force applied by ice skater and reaction is motion of skater and sled away from each other with different acceleration.
Answer:
27.82 m/s
Explanation:
The radius of the hose is half of its diameter

So its area must be

The speed of water coming out of the hose is its flow rate divided by the cross-section area of the hose

Answer: 4.9 g/cm^3
Explanation.
!) Data
mass = 49 g
Volume = 10 cm^3
2) Formula
Density = mass / volume
Density = 49 g / 10cm^3 = 4.9 g/cm^3
This is a problem where you only need to know the formula and subtitute the numbers to calculate.
The formula of density is the very same definition: mass per unit of volume.
So, as you had the mass and the volume you just need to plug the values in the formula density = mass / volume.
The net force acting on the refrigerator is 400 N to the right.
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FURTHER EXPLANATION</h3>
The net force or resultant force is the sum of all the forces acting on a body or an object in x and y axes.
- Forces along the y-axis The forces that usually act on an object vertically (in the y-axis) are: gravitational force which is a downward force and the normal force which is an upward (perpendicular) force exerted by a surface on an object resting above it that keeps the object from falling.
- Forces along the x-axis These include the force or forces applied to cause a left or right motion of an object along the horizontal plane (called the Applied Force) and the force that opposes the motion or friction.
In this problem the forces acting on the x and y - axes can be determined:
Along the x-axis:
- gravitational force = -1960 N
- normal force = +1960 N
- Net force = -1960 N + 1960 N = 0
The gravitational force is the weight of the object obtained by multiplying the mass of the object (in kg) with the acceleration due to gravity, 9.8 m/s^2. It is given a negative (-) sign to indicate that it is a downward force.
Since the object is not falling through the surface, it can be assumed that the gravitational force and normal force are balanced. Hence, the size of the normal force is the same as the gravitational force but with the opposite direction indicated by the + sign for an upward force.
The forces along the x-axis are balanced (i.e. net force is zero) so the object neither moves upward or downward.
Along the y-axis
- applied force = +400 N
- friction = 0
- Net force = +400 N + 0 = +400 N
The applied force is +400 N. It is given a + sign to indicate that its direction is to the right.
The friction, as mentioned in the problem, is set to zero or "turned off".
The net force along the y-axis is +400. The forces are unbalanced so the object will move to the right as force is applied to it.
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Keywords: net force, resultant force