Answer:
Gravity is the centripetal force when the moon orbits the earth.
Answer:
a) the distance between her and the wall is 13 m
b) the period of her up-and-down motion is 6.5 s
Explanation:
Given the data in the question;
wavelength λ = 26 m
velocity v = 4.0 m/s
a) How far from the wall is she?
Now, The first antinode is formed at a distance λ/2 from the wall, since the separation distance between the person and wall is;
x = λ/2
we substitute
x = 26 m / 2
x = 13 m
Therefore, the distance between her and the wall is 13 m
b) What is the period of her up-and-down motion?
we know that the relationship between frequency, wavelength and wave speed is;
v = fλ
hence, f = v/λ
we also know that frequency is expressed as the reciprocal of the time period;
f = 1/T
Hence
1/T = v/λ
solve for T
Tv = λ
T = λ/v
we substitute
T = 26 m / 4 m/s
T = 6.5 s
Therefore, the period of her up-and-down motion is 6.5 s
Answer:
sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j
Explanation:
We have given first vector which has length of 7 units and makes an angle of 30° with positive x-axis
So x component of the vector 
y component of the vector 
So vector will be 6.06i+3.5j
Now other vector of length of 7 units and makes an angle of 120° with positive x-axis
So x component of vector 
y component of the vector 
Now sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j
Answer:
a. 4
Explanation:
Hi there!
The equation of kinetic energy (KE) is the following:
KE = 1/2 · m · v²
Where:
m = mass of the car.
v = speed of the car.
Let´s see how would be the equation if the velocity is doubled (2 · v)
KE2 = 1/2 · m · (2 · v)²
Distributing the exponent:
KE2 = 1/2 · m · 2² · v²
KE2 = 1/2 · m · 4 · v²
KE2 = 4 (1/2 · m · v²)
KE2 = 4KE
Doubling the velocity increased the kinetic energy by 4.