1. What does the sign of a foce indicate?
A. A negative sign indicates a repulsive force, while a positive sign indicates an attractive force.
B. A negative sign indicates an attractive force, while a positive sign indicates a repulsive force.
C. A negative sign indicates a strong force, while a positive sign indicates a weak force.
D. A negative sign indicates a weak force, while a positive sign indicates a strong force.
2. Is gravitational force always attractive?
A. no, because its sign is always positive
B. yes, because its sign is always negative
C. yes, because its sign is always positive
D. no, because its sign is always negative
3. The product of m1m2 in the formula for gravitational force is always
A. negative, because the product of two negative numbers is negative.
B. positive, because the product of two positive numbers is positive.
C. negative, because the product of two positive numbers is negative.
D. positive, because the product of two negative numbers is positive.
4. What is the magnitude of the gravitational force on each mass when m1=600 kg, m2=400 kg, and their centers are 6 meters apart?
A. 4.45 X 10^-17 N
B. 6.67 X 10^-17 N
C. 2.97 X 10^-7 N
D. 6.41 X 10^-7 N
5. What is the mass of m2 when m1=860 kg, the centers of the masses are 2.4 meters apart, and the magnitude of the gravitational force on each mass is 9.07×10^−6 N?
A. m2 = 91 kg
B. m2 = 910 kg
C. m2 = 810 kg
D m2 = 107 kg
My answers
1. A
2. A
3. D
4. C
5. B
answers are
1 a negative force sign indicates an attractive force while a positive sign indicates a repulsive force
2 yes, because its sign is always negative
3 positive because the product of two positive numbers is positive
4 4.45 x 10^-7 N
5 m2=910kg
1. The correct answer is B. A negative sign indicates an attractive force, while a positive sign indicates a repulsive force.
1. The sign of a force can indicate whether it is attractive or repulsive. In the case of an attractive force, such as gravitational force or the force between opposite charges, a positive sign is used. On the other hand, a repulsive force, such as the force between like charges, is denoted by a negative sign.
2. The correct answer is C. Gravitational force is always attractive and its sign is always positive. This means that two masses will always attract each other due to gravity.
3. The correct answer is B. The product of m1m2 in the formula for gravitational force is always positive. This is because gravitational force is always attractive, and the masses involved are always positive quantities. When multiplied together, two positive numbers always yield a positive product.
4. To calculate the magnitude of the gravitational force between two masses, we can use the formula:
F = G * (m1 * m2) / r^2
where F is the gravitational force, G is the gravitational constant, m1 and m2 are the masses, and r is the distance between their centers.
Using the given values: m1 = 600 kg, m2 = 400 kg, and r = 6 meters, and using the value for the gravitational constant G = 6.67 x 10^-11 Nm^2/kg^2, we can substitute these values into the formula and solve:
F = (6.67 x 10^-11 Nm^2/kg^2) * (600 kg * 400 kg) / (6 meters)^2
F = 2.97 x 10^-7 N
Therefore, the answer is C. The magnitude of the gravitational force on each mass is 2.97 x 10^-7 N.
5. To find the mass of m2, we can rearrange the formula for gravitational force:
F = G * (m1 * m2) / r^2
Given the values: m1 = 860 kg, F = 9.07×10^−6 N, and r = 2.4 meters, we can substitute these values into the formula:
9.07×10^−6 N = (6.67 x 10^-11 Nm^2/kg^2) * (860 kg * m2) / (2.4 meters)^2
Simplifying the equation, we can solve for m2:
(860 kg * m2) / (2.4 meters)^2 = 9.07×10^−6 N / (6.67 x 10^-11 Nm^2/kg^2)
m2 = (9.07×10^−6 N / (6.67 x 10^-11 Nm^2/kg^2)) * (2.4 meters)^2 / 860 kg
Calculating this expression, we find m2 ≈ 910 kg.
Therefore, the answer is B. The mass of m2 is approximately 910 kg.