Answer:
4.04 s
Explanation:
h = vi + 1/2 a t ^2
HERE h = 80 m , vi = 0 , a =9.81 m/s^2
80 = 0 + 1/2 × 9.81 × t ^2
80 = 4.905 t^2
t^2 = 80/4.905
t ^2 = 16.30988
t = square root of 16.30988
t = 4.0385 s
t = 4.04 s
The answer would be a nail rusting, but really it could be any of these.
The incline is frictionless, this means we can use the conservation of energy: the initial kinetic energy of the block
is converted into gravitational potential energy
where h is the height reached by the block as it stops. By equalizing the two formulas, we get
However, this is the maximum height reached by the block. The distance along the surface of the plane is given by:
The answer would be:
C. An unbalanced force has acted on the vehicle.
The presence of an unbalanced force will accelerate an object, the second law of motion dictates this (Although not explicitly). Lets knock out the rest of the choices.
If a balance force acted on the vehicle, then the vehicle would be at rest. The mass of the vehicle did not change (Unless it falls apart, which I doubt). The direction of the vehicle does not change and it will only do so if another force and a stronger one at that will counteract the current net force acting on the vehicle.
Hope you got your answer here, although you did not ask for an explanation, maybe this will help you figure some of the other questions you have on your own.
When you put that into a Punnett square you first use the FOIL method because this is a dihybrid case where two traits are considered. This will be the resulting Punnett square:
PL Pl pL pl
PL PPLL PPLl PpLL PpLl
Pl PPLl PPll PpLl Ppll
pL PpLL PpLl ppLL ppLl
pl PpLl Ppll ppLl ppll
Now based on the Punnett square above, you can get the ratio. Remember that the dominant trait will always be expressed when you count phenotype combinations so as long as there is a capital letter in the combination, it will always be the one expressed.
So there are 9 polka dot, long eyelashes(PL), 3 polka dot, short eyelashes (Pl), 3 solid color, long eyelashes (pL), 1 solid short eyelashes(pl).
So your answer is D. 9:3:3:1 ratio
