Runner A because they completed it in a less amount of time
Answer:
Mass of the planet = 6.0 × 
Explanation:
Time period = 2π (R + h) / v
Orbital speed (v) = √GM / (R + h)
T² = 4π² (R + h)² / (GM/ (R + h))
= 4π² (R + h)³ / GM
making m the subject of the formula
m = 4π² (R + h)³ / GT²
= 4π² ( 6.38 ×
+ 230 × 10³ )³ / ( 6.67 ×
) × (89 × 60)²
= 4π² ( 6610000)³ / ( 6.67 ×
) × (89 × 60)²
= 5.99 × 
= 6.0 × 
Answer:
Computer hard drives use magnetism to store the data on a rotating disk. More complex applications include: televisions, radios, microwave ovens, telephone systems, and computers. An industrial application of magnetic force is an electromagnetic crane that is used for lifting metal objects.
Answer:
30 miliAmps
Explanation:
Step 1:
Obtaining an expression to solve the question. This is illustrated below:
From ohm's law,
V = IR
Were:
V is the voltage.
I is the current.
R is resistance.
From the question given, we were told that the resistance is constant. Therefore the above equation can be written as shown below:
V = IR
V/I = constant
V1/I1 = V2/I2
V1 is initial voltage.
V2 final voltage.
I1 is initial current.
I2 final current.
Step 2:
Data obtained from the question. This include the following:
Initial voltage (V1) = V
Initial current (I1) = 60 miliAmps
Final voltage (V2) = one-half of the original voltage = 1/2V = V/2
Final current (I2) =..?
Step 3:
Determination of the new current. This can be obtained as follow:
V1/I1 = V2/I2
V/60 = (V/2) / I2
Cross multiply to express in linear form
V x I2 = V/2 x 60
V x I2 = V x 30
Divide both side by V
I2 = (V x 30)/V
I2 = 30mA.
Therefore, the new current is 30miliAmps
Answer:
When the radius is doubled, its speed will be 42.42 km/h.
Explanation:
Given that,
The maximum speed around a level curve is 30 km/h = 8.34 m/s
We need to find the maximum speed around a curve with twice the radius. The maximum speed of the object is given by :
............(1)
If radius is doubled, r' = 2r
The maximum speed is given by :

..........(2)
Dividing equation (1) and (2) we get :



v' = 42.42 km/h
So, when the radius is doubled, its speed will be 42.42 km/h. Hence, this is the required solution.