Here we apply conservation of linear momentum. The momentum of the truck with cargo and without cargo remains constant. That is,
.
Here 
are initial mass and velocity. 
are final mass and velocity. Here 
and 
.
The velocity of the truck be after its cargo is taken off is
Using the given equation you get:
E = 1.99x10^-25 / 9.0x10^-6
Divide 1.99 by 9.0: 1.99/9.0 = 0.22
For the scientific notation, when dividing subtract the two exponents:
25 -6 = 19
So you now have 0.22 x 10^-19
Now you need to change the 0.22 to be in scientific notation form:
2.2 x 10^-20
The answer is B.
Answer:
Explanation:
The equation for this is
where f is the frequency, v is the velocity, and lambda is the wavelength. Filling in:
and
which means that
the wavelength is 1.37 m, rounded to the correct number of significant digits.
Answer: 
Explanation:
This problem can be solved by the following equation:
Where:
is the change in kinetic energy
is the electric potential difference
is the electric charge
Finding :
Finally:
Have everything in control and in order and discuss about different issues.
