Answer:
D) wood rubbed against a rough surface feels hot
Explanation:
The heat is transferred from one form of energy (friction of the wood being rubbed against the surface) to another (heat energy).
300 miles / 6 hours = 50 miles per hour
Answer:
3kg sledgehammer swung at 1.5 m/s
Explanation:
Small Sledgehammer:
Mass:3.0
Velocity:1.5
MASS×VELOCITY=MOMENTUM
3.0×1.5= 4.5 (momentum)
Large Sledgehammer:
Mass:4.0
Velocity:0.9
4.0×0.9=3.6 (momentum)
higher momentum is the smaller Sledgehammer.
Answer:
The difference between a physical reaction and a chemical reaction is composition. In a chemical reaction, there is a change in the composition of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition. Although we call them physical "reactions," no reaction is actually occurring. In order for a reaction to take place, there must be a change in the elemental composition of the substance in question. Thus, we shall simply refer to physical "reactions" as physical changes from now on.
Explanation:
Physical changes are limited to changes that result in a difference in display without changing the composition. Some common changes (but not limited to) are:
Texture
Color
Temperature
Shape
Change of State (Boiling Point and Melting Point are significant factors in determining this change.)
Physical properties include many other aspects of a substance. The following are (but not limited to) physical properties.
Luster
Malleability
Ability to be drawn into a thin wire
Density
Viscosity
Solubility
Mass
Volume