| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.13 |
| Score | 0% | 63% |
| 6.46 ft. | |
| 9 ft. | |
| 455 ft. | |
| 3.23 ft. |
To balance this lever the torques at the green box and the blue arrow must be equal. Torque is weight x distance from the fulcrum so the equation for equilibrium is:
Rada = Rbdb
where a represents the green box and b the blue arrow, R is resistance (weight/force) and d is the distance from the fulcrum.Solving for da, our missing value, and plugging in our variables yields:
da = \( \frac{R_bd_b}{R_a} \) = \( \frac{60 lbs. \times 7 ft.}{65 lbs.} \) = \( \frac{420 ft⋅lb}{65 lbs.} \) = 6.46 ft.
| -6.5 | |
| 1.4 | |
| 0.8 | |
| 1.5 |
The gear ratio (Vr) of a gear train is the product of the gear ratios between the pairs of meshed gears. Let N represent the number of teeth for each gear:
Vr = \( \frac{N_1}{N_2} \) \( \frac{N_2}{N_3} \) \( \frac{N_3}{N_4} \) ... \( \frac{N_n}{N_{n+1}} \)
In this problem, we have only two gears so the equation becomes:Vr = \( \frac{N_1}{N_2} \) = \( \frac{24}{16} \) = 1.5
| 0.69 ft. | |
| 2.75 ft. | |
| 11 ft. | |
| 55 ft. |
To balance this lever the torques on each side of the fulcrum must be equal. Torque is weight x distance from the fulcrum so the equation for equilibrium is:
Rada = Rbdb
where a represents the left side of the fulcrum and b the right, R is resistance (weight) and d is the distance from the fulcrum.Solving for db, our missing value, and plugging in our variables yields:
db = \( \frac{R_ad_a}{R_b} \) = \( \frac{55 lbs. \times 1 ft.}{20 lbs.} \) = \( \frac{55 ft⋅lb}{20 lbs.} \) = 2.75 ft.
When it comes to force, mass and acceleration have what kind of relationship?
logarithmic |
|
inverse |
|
exponential |
|
linear |
Newton's Second Law of Motion states that "The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object." This Law describes the linear relationship between mass and acceleration when it comes to force and leads to the formula F = ma or force equals mass multiplied by rate of acceleration.
The principle of moments defines equilibrium in terms of:
power |
|
energy |
|
speed |
|
torque |
According to the principle of moments, you can maintain equilibrium if the moments (forces) tending to clockwise rotation are equal to the moments tending to counterclockwise rotation. Another name for these moments of force is torque.