Because radio waves can travel in space but sound waves cannot.
Answer:
Explanation:
If no Energy is lost ( either as Sound energy or any other energy) the total energy of ball A equals the total energy of ball B
Therefore the Kinetic Energy of Ball B equals the Total Energy of Ball A minus the Potential Energy of Ball A
K. E = T. E - P.E
By definition, Ampere is a unit of current which is a measure of the amount of charge passing through a point in a circuit per unit of time, with an equivalent charge of 1.602 x 10^(-19) Coulomb per electron. To determine the number of electrons passing through the heater, we use the definition of the current. We calculate as follows:
13.5 A = 13.5 C per second
Charge = 13.5 C/s (10 min) ( 60 s / 1 min)
Charge = 8100 C
Number of electrons = 8100 C / 1.602 x 10^(-19) C per electron
Number of electrons = 5.1 x 10^22 electrons
Therefore, there are 5.1 x10^22 electrons that assed through the heater for 10 minutes.
Answer:
Explanation:
We know that the volume V for a sphere of radius r is
If we got an uncertainty the formula for the uncertainty of V is:
We can calculate this uncertainty, first we obtain the derivative:
And using it in the formula:
The relative uncertainty is:
Using the values for the problem:
This is, a percent uncertainty of 4.77 %
Answer:
s = 20 m
Explanation:
given,
mass of the roller blader = 60 Kg
length = 10 m
inclines at = 30°
coefficient of friction = 0.25
using conservation of energy
u = 9.89 m/s
Using second law of motion
ma =μ mg
a = μ g
a = 0.25 x 9.8
a = 2.45 m/s²
Using third equation of motion ,
v² - u² = 2 a s
0² - 9.89² = 2 x 2.45 x s
s = 20 m
the distance moved before stopping is 20 m