Answer:
k = 49 N/m
Explanation:
Given that,
Mass, m = 250 g = 0.25 kg
When the mass is attached to the end of the spring, it elongates 5 cm or 0.05 m. We need to find the spring constant. Let it is k.
The force due to mass is balanced by its weight as follows :
mg=kx

So, the spring constant of the spring is 49 N/m.
Answer:
276.135 J
Explanation:
Given that:
mass of Fe = 30.0 g
initial temperature = 24.5°C
final temperature = 45.0°C
specific heat of Fe = 0.449 J/g°C
We can determine the thermal energy added by using the formula;
Q = mcΔT
Q = 30.0g × 0.449 J/g°C × (45.0 - 24.5)°C
Q = 276.135 J
Answer:

Explanation:
The mass of one electron is

So the number of electrons contained in M=1.7 kg of mass is

The charge of one electron is

So, the total charge of these electrons is equal to the charge of one electron times the number of electrons:

Answer:
a) 6076 m
b) 43.33 m/s
c) 68 m/s
Explanation:
(a) If the airplane rounds half the circle in 156s, its displacement is the circle diameter in 156s, or twice the circle's radius
s = 2r = 2* 3.38km = 6.76 km or 6760 m
(b) The average velocity would be displacement over unit of time
v = s/t = 6760 / 156 = 43.33 m/s
(c) The length of the chord it's swept in 156s is half of the circle perimeter
c = πr = π3.38 = 10.62 km or 10620 m
The airplane average speed is its chord length over a unit of time
c / t = c / 156 = 68 m/s
Answer:
<em>a. True</em>
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Explanation:
I'll assume the question is about magnetic latches and locks.
Magnetic door locks use an electromagnetic force to stop doors from opening, so they are ideal for security. There are two main types of electric locking devices. Locking devices can either be a fail-secure locking device that remains locked when power is lost, or a fail-safe locking device that is unlocked when de-energized. An electromagnetic lock creates a magnetic field when energized or powered up, this causes an electromagnet and armature plate to become attracted to each other strongly enough to keep a door from opening.