Answer:
210
Explanation:
A ball rolls horizontally off the cliff at a speed of 30 m/s. It takes 7 seconds for the ball to hit the ground. What is the height of the cliff and the horizontal distance traveled by the ball?
S = (1/2)*9.8 m/s^2 * 7^2 = 240.1 m if the ball is very dense so air resistance, and therefore terminal velocity, can be ignored.
S = v * t = 30 m/s * 7 s = 210 m for the horizontal distance, again assuming negligible air resistance.
Answer:
9155 years old
Explanation:
We use the following expression for the decay of a substance:

So we first estimate the value of k knowing that the half-life of the C14 is 5730 years:

so, now we can estimate the age of the artifact by solving for"t" in the equation:

which we can round to 9155 years old.
Answer:
Some types of electromagnetic waves, like radio waves, microwaves, infrared waves, visible light and ultraviolet waves, can be reflectedSome types of electromagnetic waves, like radio waves, microwaves, infrared waves, visible light and ultraviolet waves, can be reflected
Explanation:
Answer:
2.5m
Explanation:
Torque is defined as the rotational effect of a force on a body.
The torque T for the maximum shear stress is given as 0.1 Nm
Frictional torque is the torque caused by a frictional force
The frictional torque F is given as 0.04 Nm/m
The maximum length of the shaft is thus given as
L = T / F
= 0.1/0.04
L= 2.5 m
Density of a material depends upon it's mass & volume.
You can calculate it by: Density = Mass / Volume
Hope this helps!