Answer: (C) The ball will accelerate to about 20 m/s.
Explanation: The ball is in free fall and no other but gravitational force acts on it. This means the ball will be subject to the gravitational acceleration, which is about 9.8 m/s^2. So after one additional second the ball will increase its velocity to (10+9.8) m/s = 19.8 m/s or approx. 20 m/s.
They seek their natural resting places
Answer:
1. MA = 4
2. MA = 2
3. MA = 6.5
4. MA = 7
5. MA = 1.8
Effort = 152.78 N
Weight = 90 N
Explanation:
The mechanical advantage of a lever is given as:
Mechanical Advantage = MA = Effort Arm/Resistance Arm
1.
MA = 12 m/3 m
<u>MA = 4</u>
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2.
MA = 2 ft/1 ft
<u>MA = 2</u>
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3.
MA = 26 cm/ 4 cm
<u>MA = 6.5</u>
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4.
Since the resistance arm is 0.5 m and the total board length is 4 m.
Therefore:
Effort Arm = 4 m - 0.5 m = 3.5 m
MA = 3.5 m/0.5 m
<u>MA = 7</u>
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5.
Effort Arm = 4.5 m
Resistance Arm = 2.5 m
MA = 4.5 m/2.5 m
<u>MA = 1.8</u>
Another formula for mechanical advantage is:
MA = Weight/Effort
here,
Weight = 275 N
Effort = ?
Therefore,
1.8 = 275 N/ Effort
Effort = 275 N/1.8
<u>Effort = 152.78 N</u>
To lift a wooden board a 50 N force is applied. Therefore,
1.8 = Weight/50 N
Weight = 50 N * 1.8
<u>Weight = 90 N</u>
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That's kind of an intuitive description of an "open circuit".