Solid substances have molecules held tightly and close together
Liquid substances have molecules moving loosely
Gaseous molecules are moving completely freely
As moleclues get further apart, i.e. As a substance changes state from solid to liquid to gas, molecules gain kinetic energy and vibrate/move more. This means they gain heat energy (the averge energy a substance has) so the temperature increases
Substances exist in different states at different temperatures and different substances will exist in different states at the same temperature. This is to do with the forces between molecules and how much heat (energy) is required to break them
Answer:
98N and 147N
Explanation:
We have the following information:
We can find the static fricton force as follow,
Where N is the normal force (mg)
Static friction force at 147N is greater than the force applied hence body does not move.
Answer:B
Explanation:Grote reber was the first scientist to map the milky way galaxy using radio waves.
In this item, we let x be the rate of the boat in still water and y be the rate of the current.
Upstream. When the boat is going upstream, the speed in still water is deducted by the speed of the current because the boat goes against the water. The distance covered is calculated by multiplying the number of hours and the speed.
(x - y)(3) = 144
Downstream. The speed of the boat going downstream is equal to x + y because the boat goes with the current.
(x + y)(2) = 144
The system of linear equations we can use to solve for x is,
3x - 3y = 144
2x + 2y = 144
We use either elimination or substitution.
We solve for the y of the first equation in terms of x,
y = -(144 - 3x)/3
Substitute this to the second equation,
2x + 2(-1)(144 - 3x)/3 = 144
The value of x from the equation is 60
<em>ANSWER: 60 km/h</em>
Answer: Boyle found that when the pressure of a gas at a constant temperature is increased, the volume of the gas decreases. When the pressure of a gas is decreased, the volume increases. This relationship between pressure and volume it's called Boyle's law.
Explanation: In the 1600s, Boyle measured the volumes of gases at different pressures. Boyle found that when the pressure of a gas at a constant temperature is increased, the volume of the gas decreases. When the pressure of a gas is decreased, the volume increases. This relationship between pressure and volume it's called Boyle's law.
