Answer:
The mass of the beam is = 29 kg.
Explanation:
A beam with mass 40 kg is shown in figure. Point S is the support point. Point B is the middle point on the beam where mass of the beam acts.
Taking moment about Point S
40 × 21 =
× 29
= 29 kg
Therefore the mass of the beam is = 29 kg.
Answer:
0.03605 V/m is the electric field in the gold wire.
Explanation:
Resistivity of the gold = 
Length of the gold wire = L = 14 cm = 0.14 m ( 1 cm = 0.01 m)
Diameter of the wire = d = 0.9 mm
Radius of the wire = r = 0.5 d = 0.5 × 0.9 mm = 0.45 mm = 
( 1mm = 0.001 m)
Area of the cross-section = 
Resistance of the wire = R
Current in the gold wire = 940 mA = 0.940 A ( 1 mA = 0.001 A)

( Ohm's law)

We know, Electric field is given by :




0.03605 V/m is the electric field in the gold wire.
The kinetic energy is transferred to thermal energy through friction
have no idea but I think the particles would be affected because they would move faster then normal and have the space to
1.) The force of gravity is what we call weight, we define it as:
w=mg
w=5,7kg*9,8m/s²
w=55,86kg (b)
2.) We know that:
power=W/t
power=50J/20s
power=2,5Watts (a)
3.) The work done is equal to the potential energy, so:
Epg=mgh
Epg=63kg*9,8m/s²*7m
Epg=4321J
Now we get the power:
power=W/t
power=4321J/5s
power=864Watts
Now:
1HP=746Watts
=1,16HP (b)
4.) We know that:
F=ma
350N=m*10m/s²
m=350N/10m/s²
m=35kg (b)
5.) d.) Aceleration is tha rate of change in velocity, either positive (increasing) or negative (decreasing)