<h2>Soccer player practices kicking the ball </h2>
The player has 15 meters per second ( m/s ) average velocity of the ball. In order to calculate, we know that the formula of calculating the velocity is velocity = displacement / time.
A player practices kicking the ball into the goal from halfway down the soccer field. Half displacement will be considered which is 45 meters and time interval is given which is 3 seconds. By putting values in the formula v = d / t ( 45 / 3 ) = 15, we get 15 m / s average velocity.
Answer:
Option C
Explanation:
Scalar quantities are described by its magnitude only. They do not need to be described by the direction. So, 20 miles per hour is the scalar quantity.
Answer:
539 N
Explanation:
Fg = mg
Step 1: Define
Fg = ?
m = 55.0 kg
g = 9.8 m/s²
Step 2: Substitute and Evaluate
Fg = 55.0 kg(9.8 m/s²)
Fg = 539 N
Math, solve fo n
0.045=n*1.6*10^-19
divide both sides by 1.6
0.028125=n*10^-19
divide both sides by 10^-19
0.028125*10^19=n
2.8125*10^17=n
Answer:
(a) 1.47 x 10⁴ V/m
(b) 1.28 x 10⁻⁷C/m²
(c) 3.9 x 10⁻¹²F
(d) 9.75 x 10⁻¹¹C
Explanation:
(a) For a parallel plate capacitor, the electric field E between the plates is given by;
E = V / d -----------(i)
Where;
V = potential difference applied to the plates
d = distance between these plates
From the question;
V = 25.0V
d = 1.70mm = 0.0017m
Substitute these values into equation (i) as follows;
E = 25.0 / 0.0017
E = 1.47 x 10⁴ V/m
(c) The capacitance of the capacitor is given by
C = Aε₀ / d
Where
C = capacitance
A = Area of the plates = 7.60cm² = 0.00076m²
ε₀ = permittivity of free space = 8.85 x 10⁻¹²F/m
d = 1.70mm = 0.0017m
C = 0.00076 x 8.85 x 10⁻¹² / 0.0017
C = 3.9 x 10⁻¹²F
(d) The charge, Q, on each plate can be found as follows;
Q = C V
Q = 3.9 x 10⁻¹² x 25.0
Q = 9.75 x 10⁻¹¹C
Now since we have found other quantities, it is way easier to find the surface charge density.
(b) The surface charge density, σ, is the ratio of the charge Q on each plate to the area A of the plates. i.e
σ = Q / A
σ = 9.75 x 10⁻¹¹ / 0.00076
σ = 1.28 x 10⁻⁷C/m²
