I would carry a 25 pound box up 5 flights, because it is lighter. You will wear out faster carrying a 50 pound box up 3 flights.
Answer:
0.003333 s to 0.000125s or from 3.33ms to 0.125ms wher m is for milli
1.1m to 0.04125 m
Explanation:
T= 1/f=
if f= 300Hz then T = 1/300 =0.003333 s
if f= 8000 then T= 1/8000 = 0.000125s
now v=f×wave length
or wavelength = speed/ frequency
when f = 300 Hz
wavelength = 330/300=1.1 m
wavelength = 330/8000 = 0.04125m
note : i have taken speed of sound as 330 m/s you can take any value given in between 330m/s to 340m/s
Answer:
1.2826 x 10^-13 m
Explanation:

Here, k be the kinetic energy and m be the mass
K = 50 KeV = 50 x 1.6 x 10^-16 J = 80 x 10^-16 J
m = 1.67 x 10^-27 kg

λ = 1.2826 x 10^-13 m
The work done by Joe is 0 J.
<u>Explanation</u>:
When a force is applied to an object, there will be a movement because of the applied force to a certain distance. This transfer of energy when a force is applied to an object that tends to move the object is known as work done.
The energy is transferred from one state to another and the stored energy is equal to the work done.
W = F . D
where F represents the force in newton,
D represents the distance or displacement of an object.
Force = 0 N, D = 20 cm = 0.20 m
W = 0
0.20 = 0 J.
Hence the work done by Joe is 0 J.