Answer:
C
Explanation:
An element is a pure substance that can not be broken down into anything simpler
A compound in also a pure substance held together in fixed proportion through chemical bonds
Answer:
Orange , yellow, green and blue
red coat absorbs all colors of visible light except red, so red light
is the only light left to bounce off of the coat toward our eyes.
Answer:
1. In a coal-fired power plant, chemical energy is first converted to thermal energy. TRUE.
The chemical energy in the coal is converted to thermal energy when the coal is burnt to produce steam.
2. In a coal-fired power plant, approximately 2/5 of original energy in the coal is lost to heat. FALSE.
Approximately 3/5 of the original energy is lost not 2/5 so this statement is false.
3. The molecules in cold air move faster than in hot air. FALSE.
Molecules with more heat move faster than molecules with less. Molecules in cold air therefore, will move slower than molecules in hot air.
Answer:
A force of μk⋅60N is needed to keep a 60-newton rubber block moving across level, dry asphalt in a straight line at a constant speed.
Explanation:
Answer:
The mass of a tennis ball is 59 grams.
Explanation:
Given that the formula for momentum is p = m×v where m represents mass (kg) and v is speed (m/s). Then, you have to substitute the values :
