A) Pure substances, Chemical changes
from kinematics equation if we know that final speed is ZERO and initial speed is given that due to constant deceleration the object will stop in some distance "d" and this distance can be calculated by kinematics
here acceleration due to friction will be same at all different speed
so for 45 km/h speed the distance of stop is 15 m
while at other speed 112.5 km/h the distance will be unknown
now we will have
now divide above two equations
So it will stop in distance 93.75 m
Answer:
Friction is a force tends to oppose relative motion between bodies when they are in direct contact. Remember this friction does not oppose motion, it opposes relative motion.
Explanation:
Answer:
There are five signs of a chemical change:
Color Change.
Production of an odor.
Change of Temperature.
Evolution of a gas (formation of bubbles)
Precipitate (formation of a solid)
Explanation:
I just went ahead and gave you the five signs of chemical change hoped it helped
Answer:
Heat generated by the current = 1547.89 J
Explanation:
We have equation for heat energy H = mCΔT
Mass of copper = 0.221 kg
Specific heat of copper = 0.093 kcal/kgC° = 389.112 J/kgC°
ΔT = 38 - 20 = 18°C
Substituting in H = mCΔT
H = 0.221 x 389.112 x 18 = 1547.89 J
Heat generated by the current = 1547.89 J
