Answer:
Initial velocity is 0 .. ( since it is just dropped)
now using V²= u² +2gh
=> (Vfinal)² = 0+2*10*20
=> v² = 20*20 = 400
=> v = √400 = 20m/s
for time taken
use V = u+gt
=> t = V/g = 20/10 = 2sec
The water. Take the specific heat of steel, estimate the volume of the nail, you know the volume of the water, which has a specific heat of one. Or be obvious. If you dropped a red hot nail into a liter of cold water, what would happen?
Answer:
Water
Answer:
C. Using controlled conditions
Explanation:
I did the quiz and B turned out to be wrong. D just doesn't make sense. Although A can be true in some experiments, it's not always the case.
Answer:
29.0 g
Explanation:
The mass of the piece of gold is given by:
m = dV
where
m is the mass
d is the density
V is the volume of the piece of gold
The density of gold is
d = 19.3 g/cm^3
while the volume of the sample is equal to the volume of displaced water, so
V = 64.5 mL - 63.0 mL = 1.5 mL
And since
1 mL = 1 cm^3
the volume is
V = 1.5 cm^3
So the mass of the piece of gold is:
m = (19.3 g/cm^3)(1.5 cm^3)=29.0 g
Answer:
the diver's speed is independent of the launch height.
Explanation:
For this exercise we must use Newton's second law
fr - W = m a
the friction force has the general form
fr = b v
Let's analyze this equation to find out what happens with the speed of the distant club.
When jumping, the initial speed is zero, so the friction force is zero and has an acceleration equal to the acceleration of gravity, as the speed increases the friction force increases decreasing the acceleration until it becomes zero, when it arrives at this value the velocity it has is called terminal velocity and this velocity remains fixed in relation to the trajectory.
fr = W
v = cte
The distance or time in which this equilibrium is reached is relatively fast, so the diver's speed is independent of the launch height.
