A carbon rod with a radius of 1.9 mm is used to make a resistor. What length of the carbon rod should be used to make a 3.7 Ω resistor? The resistivity of this material is 1.8 × 10−5 Ω · m .

Length = 2.32 m

Explanation:

Let the length required be 'L'.

Given:

Resistance of the resistor (R) = 3.7 Ω

Radius of the rod (r) = 1.9 mm = 0.0019 m [1 mm = 0.001 m]

Resistivity of the material of rod (ρ) =

First, let us find the area of the circular rod.

Area is given as:

Now, the resistance of the material is given by the formula:

Express this in terms of 'L'. This gives,

Now, plug in the given values and solve for length 'L'. This gives,

Therefore, the length of the material required to make a resistor of 3.7 Ω is 2.32 m.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards

answer; how far out of place which the object finished relative to the starting location;