Answer:
Solids: Sound travels fastest through solids. This is because molecules in a solid medium are much closer together than those in a liquid or gas, allowing sound waves to travel more quickly through it. In fact, sound waves travel over 17 times faster through steel than through air.
Explanation:
Answer:
a = 2.5 m/s²
Explanation:
given,
initial speed = 0 m/s
final speed = 25 m/s
time = 10 s
acceleration of bike is equal to change in velocity per unit time
a = 2.5 m/s²
hence, acceleration of bike is equal to a = 2.5 m/s²
<span>You can start with the equations you know
a=v^2/r = (2pi*r/T)^2/r = 4pi^2r/T^2
Radius of earth (R) = 6378.1 km
Time in one day (T) = 86400 seconds
Latitude = 44.4 degrees
If you draw a circle and have the radius going out at a 44.4 degree angle above the center you can then find the r.
r=Rcos(44.4)
r=6378.1cos(44.4)
r= 4556.978198 km or 4556978 m
Now you can plug this value into the acceleration equation from above...
a= 1.8*10^8/7.47*10^9
a= .0241 m/s^2 </span>
Over time, the types of technology can vary and be improved upon so that more advanced techniques become more valued. This could be the situation with mining whereby back in the 1500's in underground mines the rock was broken by fire setting ie lighting a fire below the rock face to heat up the rock and then throwing cold water on it to crack it, so that it could be dug by hand. With the advent of explosives, this all changed so that the rock could be blasted. The increase in advance rates for an underground heading have thus gone from 5-20 feet per month to up to 300meters (984 ft) per month for a 24/7 mining operation, which is a huge improvement.
Answer:
The work done on the system can be accounted for by;
Both 
and 
Explanation:
The speed of the crate = Constant
Therefore, the acceleration of the crate = 0 m/s²
The net force applied to the crate, 
= 0
Therefore, the force of with which the crate is pulled = The force resisting the upward motion of the crate
However, we have;
The force resisting the upward motion of the crate = The weight of the crate + The frictional resistance of the ramp due to the surface contact between the ramp and the crate
The work done on the system = The energy to balance the resisting force = The weight of the crate × The height the crate is raised + The heat generated as internal energy to the system
The weight of the crate × The height the crate is raised = Gravitational Potential Energy =
The heat generated as internal energy to the system =
Therefore;
The work done on the system = + .
