Answer:
A) If the paintball stops completely the magnitude of the change in the paintball’s momentum is 
B) If the paintball bounces off its target and afterward moves in the opposite direction with the same speed, the change in the paintball’s momentum is 
C) A paintball bouncing off your skin in the opposite direction with the same speed hurts more than a paintball exploding upon your skin because of the strength exerted is twice than if it explodes.
Explanation:
Hi
A) We use the formula of momentum
, so we have 
B) We use the same formula above, then due we have a change of direction at the same speed, therefore the change in the momentum is the double so
.
C) The average strength of the force an object exerts during impact is determined by the amount the object’s momentum changes. therefore
, as we don't have any data about the impact time but we know momentum is twice, time does no matter and strength is twice too.
If the wavelength increases (gets longer), then the frequency <em>decreases</em>.
(A wave occurs less often.)
Answer:
4. To the east
Explanation:
Friction forces always act in the opposite direction that an object tends to move in. In this case, when the truck accelerates to the east, the crate tends to move to the west due to inertia (the tendency for an object to remain at rest or at constant speed). In order to stop the crate from moving, there needs to be a friction force to the east.
Answer:
Explanation: The periodic table contains rows and columns. To find how many valence electrons are in an element, simply locate the column number that it is in, and that determines the number of valence electrons in an element. This rule works only for elements excluding the transition metals
Explanation: