Answer:
Fr = 20 (N)
Explanation: See atached file ( free body diagram)
As for Newton´s low
∑ Fy = 0
-mg + N = 0 ⇒ - 40 + N = 0 ⇒ N = 40 [Newtons]
by definition : Fr = μs * N ⇒ Fr = 0,5 * 40 ⇒ Fr = 20 (N)
∑ Fx = 0 body is at rest
Fe - Fr = 0
Fr > Fe
Fr > 12 (N) the body is at rest
Answer:
length is 23.228091 m
Explanation:
Given data
radius = 0.791 mm = 0.791 × m
current = 9.25 A
voltage = 1.20 × 10² V
to find out
resistance and length of wire
solution
we know the resistance formula that is
resistance = voltage / current
resistance = 1.20 × 10² /9.25
resistance = 12.97
so resistance is 12.97 ohm
and length of nichrome wire formula is
length = resistance × area / specific resistance of wire
so specific resistance of wire we know = 1.1 ×
and area = × r² =
× (0.0791×
)²
area = 1.97 ×
length = 12.97 × 1.97 × / 1.1 ×
so length is 23.228091 m