thw answer is C. 2
i do not know why! Sorry!
i just took the test and it was right
Answer:
12.5 ft/s
Explanation:
Height of person = 6 ft
height of lamp post = 10 ft
According to the question,
dx / dt = 5 ft/s
Let the rate of tip of the shadow moves away is dy/dt.
According to the diagram
10 / y = 6 / (y - x)
10 y - 10 x = 6 y
y = 2.5 x
Differentiate both sides with respect to t.
dy / dt = 2.5 dx / dt
dy / dt = 2.5 (5) = 12.5 ft /s
Answer:
Constructive interference
Explanation:
Here, the medium is same, same wavelength, same frequency, same amplitude and same direction of propagation.
Let the intensity of waves be I which is same for both
The formula for the net intensity is
where, Ф be the phase difference
So, 
Here, IR is maximum so the interference is constructive in nature.
Answer:
The correct answer is V√5
Explanation:
Let V be the velocity of the satellite orbiting at radius r.
Let V(5r) be the velocity of the satellite orbiting at radius 5r.
Recall:
Escape velocity is given by:
V = √(2gr)
Where V is the escape velocity
g is the acceleration due to gravity
r is the radius of the earth.
With the above equation, we can obtain the answer to the question as follow:
V = √(2gr)
V(5r) = √(2g5r)
Next, we'll obtained the ratio of V(5r) to V as shown below
V(5r) : V => V(5r)/V
V(5r)/V = √(2g5r) / √(2gr)
V(5r)/V = √5
Cross multiply
V(5r) = V√5
From the above illustration, we can see that when the satellite is moved to 3r, then the expression for the velocity will be V√5
Discrete means something thats seperate or distant from something
Continuous charge distrubution means voltage at any point in space produced by a continuous charge
