Change in velocity = Final velocity - Initial velocity
Initial velocity = 20 m/s
Final velocity = 10 m/s
Change in velocity = 10 - 20 = -10m/s
Correct option B
Hope This Helps You!
Answer:
E) 80 N/m
Explanation:
Given;
mass of the block, m = 4.8 kg
displacement of the block, x = -0.5 m
velocity of the block, v = -0.8 m/s
acceleration of the block, a = 8.3 m/s²
From Newton's second law of motion;
F = ma
Also, from Hook's law;
F = -Kx
where;
k is the force constant
Thus, ma = -kx
k = -ma/x
k = -(4.8 x 8.3) / (-0.5)
k = 79.7 N/m
k ≅ 80 N/m
Therefore, the force constant of the spring is closest to 80 N/m
Answer:
a) Height of the antenna (in m) for a radio station broadcasting at 604 kHz = 124.17 m
b)Height of the antenna (in m) for radio stations broadcasting at 1,710 kHz =43.86 m
Explanation:
(a) Radiowave wavelength= λ = c/f
As we know, Radiowave speed in the air = c = 3 x 10^8 m/s
f = frequency = 604 kHz = 604 x 10^3 Hz
Hence, wavelength = (3x10^8/604x10^3) m
λ
= 496.69 m
So the height of the antenna BROADCASTING AT 604 kHz = λ /4 = (496.69/4) m
= 124.17 m
(b) As we know , f = 1710 kHz = 1710 x 10^3 Hz (1kHZ = 1000 Hz)
Hence, wavelength = λ = (3 x 10^8/1710 x 10^3) m
λ= 175.44 m
So, height of the antenna = λ /4 = (175.44/4) m
= 43.86 m
Answer:
he same direction the magnitude of the resultant is equal to the scalar sum of the magnitude of the forces, but if they are applied in different directions the magnitude must be found using the Pythagorean theorem
Explanation:
When there are several applied forces, if they are all in the same direction the magnitude of the resultant is equal to the scalar sum of the magnitude of the forces, but if they are applied in different directions the magnitude must be found using the Pythagorean theorem, so which the resulting dowry is less than the sum of the magnitudes.
Let's carry out an example with two forces, F1 and F2 of equal magnitudes
if they are in the same direction
F_total = F₁ + F₂ = 2 F
if they are at 90º
F_total = 
if they are at 180º
F_total = F₁ -F₂ = 0
lake effect snow is the correct answer
