<span>
if it was possible to triangulate all objects it would give the most accurate answer. So yes, it is the prefered method. However as this is not the case other methods are used, less accurate but more practical</span>
Answer:
Required charge
.

Explanation:
Given:
Diameter of the isolated plastic sphere = 25.0 cm
Magnitude of the Electric field = 1500 N/C
now
Electric field (E) is given as:

where,
k = coulomb's constant = 9 × 10⁹ N
q = required charge
r = distance of the point from the charge where electric field is being measured
The value of r at the just outside of the sphere = 
thus, according to the given data

or

or
Required charge
.
Now,
the number of electrons (n) required will be

or

or

Answer:
v_f = 6.92 x 10^(4) m/s
Explanation:
From conservation of energy,
E = (1/2)mv² - GmM/r
Where M is mass of sun
Thus,
E_i = E_f will give;
(1/2)mv_i² - GmM/(r_i) = (1/2)mv_f² - GmM/(r_f)
m will cancel out to give ;
(1/2)v_i² - GM/(r_i) = (1/2)v_f² - GM/(r_f)
Let's make v_f the subject;
v_f = √[(v_i)² + 2MG((1/r_f) - (1/r_i))]
G is Gravitational constant and has a value of 6.67 x 10^(-11) N.m²/kg²
Mass of sun is 1.9891 x 10^(30) kg
v_i = 2.1×10⁴ m/s
r_i = 2.5 × 10^(11) m
r_f = 4.9 × 10^(10) m
Plugging in all these values, we have;
v_f = √[(2.1×10⁴)² + 2(1.9891 x 10^(31)) (6.67 x 10^(-11))((1/(4.9 × 10^(10))) - (1/(2.5 × 10^(11)))] 20.408 e12
v_f = √[(441000000) + 2(1.9891 x 10^(30)) (6.67 x 10^(-11))((16.408 x 10^(-12))]
v_f = √[(441000000) + (435.38 x 10^(7))
v_f = 6.92 x 10^(4) m/s
Answer:

Explanation:
0.2 rev/s = 0.2 rev/s * 2π rad/rev = 0.4π rad/s
Since the angular acceleration is assumed to be constant, and the wheel's angular speed is increasing from rest (0 rad/s) to 0.4π rad/s within 23.8s. Then the angular acceleration must be
Answer:
<em>The input power is 200 W</em>
Explanation:
<u>Motor Efficiency</u>
The efficiency of a motor can be calculated as follows:

Where:
β = efficiency
Po = Output power
Pi = Input power
Solving for Pi:

The efficiency is β=0.75 and the output power is Po=150 W, thus the input power is:


The input power is 200 W