Answer:
<em>0.45 mm</em>
Explanation:
The complete question is
a certain fuse "blows" if the current in it exceeds 1.0 A, at which instant the fuse melts with a current density of 620 A/ cm^2. What is the diameter of the wire in the fuse?
A) 0.45 mm
B) 0.63 mm
C.) 0.68 mm
D) 0.91 mm
Current in the fuse is 1.0 A
Current density of the fuse when it melts is 620 A/cm^2
Area of the wire in the fuse = I/ρ
Where I is the current through the fuse
ρ is the current density of the fuse
Area = 1/620 = 1.613 x 10^-3 cm^2
We know that 10000 cm^2 = 1 m^2, therefore,
1.613 x 10^-3 cm^2 = 1.613 x 10^-7 m^2
Recall that this area of this wire is gotten as
A = 
where d is the diameter of the wire
1.613 x 10^-7 = 
6.448 x 10^-7 = 3.142 x 
=
d = 4.5 x 10^-4 m = <em>0.45 mm</em>
Answer:
There is an inward force acting on the can
Explanation:
This inward force is known as Centripetal force and it is responsible for making the can whirl on the end of a string in circle and it is also directed towards the center around which the can is moving.
Answer: economies are the strongest when workers have specialized skills
Explanation:
Answer:
They had the same speed.
Explanation:
It won't be velocity, because velocity is a vector quantity. Speed is scalar.
Answer:
13.9
Explanation:
Apparent weight is the normal force. Sum of the forces on the alloy when it is submerged:
∑F = ma
N + B − W = 0
N + ρVg − mg = 0
6.6 + (0.78 × 1000) V (9.8) − (0.750) (9.8) = 0
V = 9.81×10⁻⁵
If x is the volume of the first material, and y is the volume of the second material, then:
x + y = 9.81×10⁻⁵
(7.87×1000) x + (4.50×1000) y = 0.750
Two equations, two variables. Solve with substitution:
7870 (9.81×10⁻⁵ − y) + 4500 y = 0.750
0.772 − 7870 y + 4500 y = 0.750
0.0222 = 3370 y
y = 6.58×10⁻⁶
x = 9.15×10⁻⁵
The ratio of the volumes is:
x/y = 13.9
