Answer:
In cold air, the molecules mover slower because of the colder tempature, however, in hot air they move faster this is because the molecules are being heated up. Hot = faster, cold = slower
Explanation:
a graduated cylinder
an eye dropper
a beaker
a buret
Answer: a buret
A graduated cylinder and a beaker cannot be used. This is because the basic solution needs to be added drop by drop. This is not possible using a graduated cylinder or a beaker because it is difficult to pour drop by drop from these. An eye dropper cannot be used because it does not measure the volume being added.
A buret would be the best choice because it precisely measures the amount being added and we can add the basic solution to the acid drop by drop.
300 J
400 J
1000 J
Answer:
The K.E of the pendulum is, K.E = 200 J
Explanation:
Given data,
The kinetic energy of the bob of the pendulum at the bottom, K.E = 600 J
The potential energy at the height 4 m, P.E = 400 J
According to the conservation of energy, the total energy of the mechanical system should be conserved.
At the bottom of the swing, the entire mechanical energy of the pendulum is purely kinetic. Therefore the total energy
E = P.E + K.E
= 0 + 600 J
= 600 J
Therefore, the total energy of the system, E = 600 J
At height 4 m, the total energy of the system remains the same.
Therefore,
600 J = 400 J + K.E
K. E = 600 J - 400 J
= 200 J
Hence, the K.E of the pendulum is, K.E = 200 J
c. Modern view
b. Earth-centered
d. all of the above are solar system models
Correct answer choice:
B. Earth-centered
Explanation:
Heliocentric theory is the planetary model in which the Earth and planets rotate around the Sun at the focus of the Solar System. Historically, Heliocentric theory was objected to geocentric theory, which set the Earth at the core. This approach was explained in sections by several cosmologists over various times, particularly Aristarchus, Copernicus, Kepler, and Galileo.
Answer:
The correct answer is option b, Earth centered
Explanation:
For the very first it was proposed by Copernicus that it is not the earth but sun which lies at the center of the system and rest all planets revolve around the sun. This sun centered model is known as heliocentric system and is also referred to as the modern view. This model was also helpful in solving two major queries instantly –
a) Varying brightness of planets
b) Retrograde motion.
Answer: A. The forces on an object in motion are balanced.
Explanation:
The dynamic equilibrium is defined as the phase when an object moves at a constant velocity such that all forces on the object are balanced.
Simple case of dynamic equilibrium: A horizontal force is applied to an object making it run with a constant velocity across a surface.
Hence, the statement describes dynamic equilibrium is " The forces on an object in motion are balanced. "
So, the correct option is "A".
Answer:
Hope this helps!