Answer:
0.43 m
Explanation:
Angle of incident and angle of reflection is same.
tan Θh = L' / x (eye)
L' = Length of the window
x (eye) = Distance of the mirror from the eye
tan Θh = L / (x (eye) + xw)
xw = Distance of the mirror from the window
L'/ x (eye) = L / ( x (eye) + xw)
L' = L*x (eye) / ( x (eye) + xw)
L' = (2*0.5) / (0.5 + 1.8)
L' = 0.43 m
Answer:
If both the radius and frequency are doubled, then the tension is increased 8 times.
Explanation:
The radial acceleration (
), measured in meters per square second, experimented by the moving end of the string is determined by the following kinematic formula:
(1)
Where:
- Frequency, measured in hertz.
- Radius of rotation, measured in meters.
From Second Newton's Law, the centripetal acceleration is due to the existence of tension (
), measured in newtons, through the string, then we derive the following model:
(2)
Where 
is the mass of the object, measured in kilograms.
By applying (1) in (2), we have the following formula:
(3)
From where we conclude that tension is directly proportional to the radius and the square of frequency. Then, if radius and frequency are doubled, then the ratio between tensions is:
(4)
If both the radius and frequency are doubled, then the tension is increased 8 times.
The formula of net Force is:F = mawhere m is the mass of the objecta is the acceleration of the object
thus, if we triple the net force applied to the object:
3F = maa = 3F / m
The acceleration is also tripled since the force is directly proportional to the acceleration.
Answer:
a) The perimeter of the rectangle is 29.4 centimeters.
b) The uncertainty in its perimeter is 0.8 centimeters.
Explanation:
a) From Geometry we remember that the perimeter of the rectangle (
), measured in centimeters, is represented by the following formula:
(1)
Where:
- Width, measured in centimeters.
- Length, measured in centimeters.
If we know that 
and 
, then the perimeter of the rectangle is:
The perimeter of the rectangle is 29.4 centimeters.
b) The uncertainty of the perimeter (
), measured in centimeters, is estimated by differences. That is:
(2)
Where:
- Uncertainty in width, measured in centimeters.
- Uncertainty in length, measured in centimeters.
If we know that 
and 
, then the uncertainty in perimeter is:
The uncertainty in its perimeter is 0.8 centimeters.
