Answer:
Heat is added to a substance, but its temperature does not rise. Which one of the following statements provides the best explanation for this observation? the substance must be a gas. the substance must be a non-perfect solid. the substance undergoes a change of phase. the substance has unusual thermal properties. the substance must be cooler than its environment.
Answer: C
Explanation:
A bird flying in the air is 3D motion as the bird move up, down, right, left all the possible direction. A leaf falling from a tree is also a 3D motion because a leaf never fall in absolute vertical manner. A lady bug crawling on a soccer ball also 3D. If lady bug crawling on a plane like floor then it is 2D but now lady bug crawling on soccer ball which is in spherical shape so it is also 3D motion. Only train travelling along a track is 2D because train cannot move up and down and the track of train is in a plane. So it is 2D motion.
Answer:
or 0.07163 T into the page
Explanation:
m = Mass of particle = 10 g
a = Acceleration due to gravity = -9.8j m/s²
v = Velocity of particle = 19i km/s
q = Charge of particle = 72 μC
B = Magnetic field
Here the magnetic and gravitational forces on the particle are applied in the opposite direction so,




The magnetic field is 0.07163 T into the page
Gravitational force is a non-contact force.