Opposite charges attract; like charges repel :)
Answer:
Sound energy is produced when an object vibrates. The sound vibrations cause waves of pressure that travel through a medium, such as air, water, wood or metal. Sound energy is a form of mechanical energy.
Explanation:
Gravity increased the downward speed (or decreases the upward speed) by 9.8 m/s every second.
21.2/9.8 = 2.2 seconds
Answer:
1.551×10^-8 Ωm
Explanation:
Resistivity of a material is expressed as shown;.
Resistivity = RA/l
R is the resistance of the material
A is the cross sectional area
l is the length of the wire.
Given;
R = 0.0310 Ω
A = πd²/4
A = π(2.05×10^-3)²/4
A = 0.000013204255/4
A = 0.00000330106375
A = 3.30×10^-6m
l = 6.60m
Substituting this values into the formula for calculating resistivity.
rho = 0.0310× 3.30×10^-6/6.60
rho = 1.023×10^-7/6.60
rho = 1.551×10^-8 Ωm
Hence the resistivity of the material is 1.551×10^-8 Ωm
<u>Answers</u>
(a) 6.75 Joules.
(b) 5.27 m/s
(c) 0.75 Joules
<u>Explanation</u>
Kinetic energy is the energy possessed by a body in motion.
(a) its kinetic energy at A?
K.E = 1/2 mv²
= 1/2 × 0.54 × 5²
= 6.75 Joules.
(b) its speed at point B?
K.E = 1/2 mv²
7.5 = 1/2 × 0.54 × V²
V² = 7.5 ÷ 0.27
= 27.77778
V = √27.77778
= 5.27 m/s
(c) the total work done on the particle as it moves from A to B?
Work done = 7.5 - 6.75
= 0.75 Joules
