Answer:
The lifeguard takes 25.9 seconds to reach the child, at 25.9 meters from the start point downstream.
Explanation:
As the image shows, the child trajectory, the lifeguard trajectory and the distance from the bank form a triangle. This triangle is formed by the distances, an we already know the distance from the bank and the speed of child, and the speed of the lifeguard. So we have unknom time in common. Lets see the equations:
Using phitagoras theorem
Hello.
A chemical change is always associated with the change of the chemical components.
A physical change is associated with the change of the estate(solid, liquid, gaseous).
We can infer that when the butter melts in the sun, we have the state change <em>solid → liquid</em>, but it is still butter. Therefore, the melting is a <em>Physical Change.</em>
Answer:
The magnetic flux through the coil is greatest when the plane of its area is perpendicular to the magnetic field
Explanation: from the formula magnetic flux @= BScos∆
At perpendicular ∆ will be zero making cos∆ =1
Answer:
Explanation:
Knowing that the volume of a sphere is V=(4/3)πr³ and
We must find when r=14cm
V=(4/3)πr³ ⇒
and r=14cm then
Note: as you can see the relationship of change of r with respect to t is negative because it is a decrease, and also its volume ratio