1. lifts it chest high
The force opposing to this action is the force due to
gravity. Therefore the work done is:
W1 = m g d
where m is mass of the barbell, g is gravity and d is displacement
2. holds it for 30 seconds
Work is a product of force and displacement, since there
is no displacement, therefore work done is zero.
W2 = 0
3. puts it down slowly
If the barbell was dropped, then it would simply be a free
fall. But since it was not, so the work done here is also equal to the weight
of the barbell times displacement:
W3 = m g d
We can see that W1 = W3, and since W2 = 0, therefore the answer
is:
<span>w3 = w1 > w2</span>
Answer:
see below
Explanation:
First: Leave a couple inches of wire loose at one end and wrap most of the rest of the wire around iron u-shaped bar and make sure not to overlap the wires.
Second:Cut the wire (if needed) so that there is about a couple inches loose at the other end too.
Third: Now remove about an inch of the plastic coating from both ends of the wire and connect the one wire to one end of a battery and the other wire to the other end of the battery.
Answer:
The magnetic field strength and the electrons' energy are 0.077 T and 0.8906 eV.
Explanation:
Given that,
Diameter = 2.62 mm
Frequency = 2.15 GHz
(A). We need to calculate the magnetic field strength
Using formula of the magnetic field strength
Where, f = frequency
e = charge of electron
Put the value into the formula
(B). We need to calculate the energy of electron
Using formula of energy
The energy in eV
Hence, The magnetic field strength and the electrons' energy are 0.077 T and 0.8906 eV.
