Answer:
Radiation pressure
Explanation:
Radiation pressure is gotten from the light source. The radiation pressure has a set mass limit of 150 solar masses. Any mass from 150 solar masses or below supports the formation of the stars.
However when the mass exceeds 150 solar masses the force of gravity is unable to hold the masses together and the excess mass
Is usually blown away after which the required mass is then used in the formation.
Answer:
Work done by the spring is negative
Explanation:
We can answer this question by thinking what is the force acting on the box.
In fact, the force acting on the box is the restoring force of the spring, which is given by Hooke's Law:

where
k is the spring constant
x is the displacement of the box with respect to the equilibrium position of the spring
The negative sign in the equation indicates that the direction of the force is always opposite to the direction of the displacement: so, whether the spring is compressed or stretched, the force applied by the spring on the box is towards the equilibrium position.
The work done by the restoring force is also given by

where
F is the restoring force
x is the displacement
is the angle between the direction of the force and the displacement
Here we know that the force is always opposite to the displacement, so

Which means that the work done by the spring is always negative, since the direction of the restoring force is always opposite to the direction of motion.
Answer:
For a plant cell: The cell wall and the cell membrane
For animal cells: Just the cell membrane
Answer:

Explanation:
When activated, the receptor most likely prompting the production of saliva is the taste receptor. When food enters the mouth, the salivary glands produce the saliva upon the sensation of taste.
Electromagnetic waves are the waves that can travel without a material medium.