What is the work required to raise a 10. kg object from the surface of the Earth to a height of 2.0 m?
5.0 J
20. J
2.0 E2 J
2.0 E3 J
My answer was 20. J but this was wrong. Is the answer 2.0 E2 J?
A net force of 9.0 N acts through a distance of 3.0 m in a time of 3.0 s. The work done is?
3.0 J
9.0 J
27 J
81 J
My answer was 9.0 J but again this was wrong. Is the answer 81 J?
1) E=weight*h=10g*2=20g which is approx 196N so sthe best answer is 2.0E2 J
2) work=force*distance=9*3J
2.0 E2 J
convert 10 kg to Newtons
10 kg = 98.0665 Newtons
W = F(d)
W = 98.0665 (2)
W = 196.133
W = 2.0 E2 J when rounded
27J
W = F (d)
W = 9.0N (3.0m)
W = 27J
Time doesn't matter here
To calculate the work done, we can use the formula:
Work = Force x Distance x cos(theta)
For the first question, raising a 10. kg object to a height of 2.0 m, we need to find the force required to lift the object against gravity.
Force = mass x gravity
Where gravity is approximately 9.8 m/s^2.
Force = 10. kg x 9.8 m/s^2 = 98. N
Now we can calculate the work done:
Work = Force x Distance x cos(theta)
Since the object is being lifted vertically, the angle between the force and displacement is 0 degrees.
Work = 98. N x 2.0 m x cos(0°)
Since the cos(0°) is equal to 1, we can simplify:
Work = 98. N x 2.0 m x 1 = 196. J
The correct answer is therefore 196 J, which is not listed in the given options. None of the provided options is correct.
For the second question, we are given the force (9.0 N), distance (3.0 m), and time (3.0 s). Since the force and displacement are in the same direction, the angle between them is 0 degrees.
Using the formula:
Work = Force x Distance x cos(theta)
Work = 9.0 N x 3.0 m x cos(0°)
Again, since the cos(0°) is equal to 1, we can simplify:
Work = 9.0 N x 3.0 m x 1 = 27. J
The correct answer is 27 J, which matches one of the provided options.
To calculate the work required to raise an object from the surface of the Earth to a certain height, you can use the equation:
Work = Force × Distance
In this case, the force required to lift the object is equal to its weight. The weight can be calculated using the formula:
Weight = mass × gravitational acceleration
The mass of the object is given as 10 kg, and the gravitational acceleration on Earth is approximately 9.8 m/s^2. Therefore, the weight is:
Weight = 10 kg × 9.8 m/s^2 = 98 N
Next, you need to calculate the distance the object is being raised. In this case, it is being raised to a height of 2.0 m.
With the weight and distance known, you can now calculate the work required:
Work = Force × Distance = 98 N × 2.0 m = 196 J
Therefore, the correct answer is 196 J, which is not one of the options given. It seems that none of the provided options match the correct answer for the first question.
Moving on to the second question, to calculate work when a force is applied over a distance, you can again use the equation:
Work = Force × Distance
In this case, the force is given as 9.0 N and the distance is given as 3.0 m. Therefore, the work done is:
Work = 9.0 N × 3.0 m = 27 J
Hence, the correct answer for the second question is 27 J, which matches one of the options given. Therefore, 27 J is the correct answer.