Answer:
Explained
Explanation:
When the barbell is accelerated upward, the force exerted by the athlete is greater than the weight of the barbell. (The barbell, simultaneously, pushes with greater force against the athlete.) When acceleration is downward, the force supplied by the athlete is less than the force applied by the barbell on the athlete.
Explanation :
It is given that, the driver accelerates from a stop sign, cruises for 20 s at a constant speed of 60 km/h, and then brakes to come to a stop 40 s after leaving the stop sign.
We know that acceleration is defined as the rate of change of velocity.

Where
dv is the change in velocity, dv = 0 - 60 m/s = -60 m/s
dt is the change in time, dt = 40 s - 30 s = 10 s
So, 

From the graph it is clear that, from 30 s to 40 s the car is decelerating. So, at every second within this time the value of acceleration will be same i.e.
.
Answer:
Solid at room temperature
Explanation
Since these elements are metals they must be said at room temperature
Answer:
ΔL = L0 C ΔT
We need to find C the constant of expansivity
C = ΔL / (L0 ΔT)
C = .96 / (15.04 * 65) = 9.82 * 10^-4 / deg C
Hippity hoppity your points are my property