The answer is:
Forces acting on the sled are paired with equal and opposite forces.
The explanation:
About to push you, this means that he doesn't push yet. If the sled is on level ground and no one is pushing it, then forces are equal and opposite.
The gravity force pulls down and the ground pushes up.
This is Newton's third law:
Newton's third law: If an object A exerts a force on object B, then object B must exert a force of equal magnitude and opposite direction back on object A.
This law represents a certain symmetry in nature: forces always occur in pairs, and one body cannot exert a force on another without experiencing a force itself.
We can also see Newton’s third law at work by taking a look at how people move about. Consider a swimmer pushing off from the side of a pool.
Answer:
Explanation:
When the positively charged half shell is brought in contact with the electroscope, its needle deflects due to charge present on the shell.
When the negatively charged half shell is brought in contact with the positively charged shell , the positive and negative charge present on each shell neutralises each other .So both the shells lose their charges .The positive half shell also loses all its charges
When we separate the half shells , there will be no deflection in the electroscope because both the shell have already lost their charges and they have become neutral bodies . So they will not be able to produce any deflection in the electroscope.
Answer:
The speed of sound is affected by temperature and humidity. Because it is less dense, sound passes through hot air faster than it passes through cold air. ... The attenuation of sound in air is affected by the relative humidity. Dry air absorbs far more acoustical energy than does moist air.
Answer:
A) 667 J
B) 381.4 J
C) 0 J
D) 245.4 J
E) 40.2J
F) 2 m/s
Explanation:
Let g = 9.81 m/s2
A) The work done on the suitcase is the product of the force applied and the distance travelled:
w = Fs = 145 * 4.6 = 667 J
B) The work done by gravitational force the dot product between the gravity vector and the distance vector
C) As the normal force vector is perpendicular to the distance vector, the work done by the normal force is 0
D) The work done on the suitcase by friction force is the product of the force applied and the distance travelled, whereas friction force is the product of normal force and coefficient
E) The total workdone on the suite case would be the pulling work subtracted by gravity work and friction work
F) As the suit case has 0 kinetic and potential energy at the bottom, and the total work done is converted to kinetic energy at 4.6 m along the ramp, we can conclude that: