Answer:
b. a massive collapsed star
Explanation:
A black hole in the universe is nothing but a massive collapsed star. When the size of the star crosses a particular limit it cannot holds its mass and it collapses under it own self. This is called supernova. A black hole is actually a region in space where gravity is so strong that even light cannot escape through it. Gravity so strong because the matter has been pressed into a tiny space. hence option b is correct
Answer:
t = 1.58 s
Explanation:
given,
Speed of ranger, v = 56 km/h
v = 56 x 0.278 = 15.57 m/s
distance, d = 65 m
deceleration,a = 3 m/s²
reaction time = ?
using stopping distance formula


t is the reaction time

t = 1.58 s
hence, the reaction time of the ranger is equal to 1.58 s.
because detergent has to clean dirt outa clothes and tooth pste also can help get stains outa cloths and when you put those two mixtures tofgether it can make the ultimate cleaning mixture
Answer: A. Work is done on the system and heat is transferred from the system for a net decrease in internal energy.
Explanation:
A refrigerator is a device which dispenses heat from the close system to a warmer area or in the surrounding. By dispensing the heat the internal temperature of the refrigerator drops. The system of refrigerator violates the second law of thermodynamics. As it performs the work to cool the region instead of heating the region. The work is done on the system and the internal energy decreases and the heat energy is liberated to the surrounding area. A refrigerator is an open system.
That's ONLY true when the pendulum is hanging
in the center position and not moving.