<span>In order for the results to be valid, the dependent variable can only be affected by the independent variable, so somethings need to be kept constant. The things that need to be kept constant are called controlled variables.</span>
Atomic disguise makes helium look like hydrogen. ... A helium atom consists of a nucleus containing two positively charged protons and two neutrons, encircled by two orbiting electrons which carry a negative charge. A hydrogen atom has just one proton and one electron
Answer:
spring compressed is 0.724 m
Explanation:
given data
mass = 1.80 kg
spring constant k = 2 × 10² N/m
initial height = 2.25 m
solution
we know from conservation of energy is
mg(h+x) = 0.5 × k × x² ...................1
here x is compression in spring
so put here value in equation 1 we get
1.8 × 9.8 × (2.25+x) = 0.5 × 2× 10² × x²
solve it we get
x = 0.724344
so spring compressed is 0.724 m
The force equation can easily prove this. F=ma. This states that the force on an object is equal to mass times acceleration. If the mass stays the same and the velocity of the cars increases than that means there is a larger force. This is because in both cases the cars are stopping in almost an instant and the times of the crashes are theoretically identical. Acceleration is the change in velocity over time. If the velocity is higher with the same amount of time than that means there is a higher acceleration. If you plug a higher acceleration into the force equation then you wind up with a higher force and in turn a more damaging collision.
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Answer:
4 km/hr
Explanation:
The computation of the actual velocity is shown below:
Because the path of its paddles is opposed to the current direction, the real velocity can be determined by deducting the current velocity to its velocity while paddling
So, the actual velocity is
= Upstream - downstream
= 19 km/hr - 15 km/hr
= 4 km/hr
As we can see it is in positive, so it is an upstream direction
