Which of the following best describes the sum of all forces acting on an object?(1 point)
Responses
net force, which is a scalar sum
net force, which is a scalar sum
net force, which is a vector sum
net force, which is a vector sum
acceleration, which is a vector sum
acceleration, which is a vector sum
gravitational force, which is a vector sum
The correct answer is net force, which is a vector sum.
Suppose a man is sitting on a chair and exerting 100 N of force downward, while a spring beneath the chair exerts 150 N of force upward. If you assign a negative value to the downward force, what is the net force of this system?(1 point)
Responses
-50 N
-50 N
50 kg
50 kg
50 N
50 N
250 N
The net force of this system can be calculated by subtracting the downward force from the upward force:
Net force = Upward force - Downward force
= 150 N - (-100 N)
= 150 N + 100 N
= 250 N
Therefore, the net force of this system is 250 N.
During a game of pool, a cue ball travels to the left with 70 N of force and collides with the four ball moving with a force of 50 N to the right. If you assign a negative value to the force moving to the right, what is the net force of this system?(1 point)
Responses
-20 N
-20 N
20 m/s2
20 m/s2
20 N
20 N
120 N
To determine the net force, we need to calculate the sum of the individual forces.
The cue ball exerts a force of 70 N to the left, while the four ball exerts a force of 50 N to the right.
Net force = Force exerted by the cue ball - Force exerted by the four ball
= 70 N - (-50 N)
= 70 N + 50 N
= 120 N
Therefore, the net force of this system is 120 N.
Recall that the formula for momentum is:
P=mv
Which of the following correctly shows momentum being calculated?
(1 point)
Responses
45 kg*m/s=(9 kg) (5 m/s)
45 kg * m / s = ( 9 kg ) ( 5 m / s )
4 kg*m/s=(9 kg) (5 m/s)
4 kg * m / s = ( 9 kg ) ( 5 m / s )
14 kg*/s=(9 kg) (5 m/s)s
14 kg * / s = ( 9 kg ) ( 5 m / s ) s
45 N=(9 kg) (5 m/s)
The correct option for the calculation of momentum using the given formula is:
45 kg * m / s = ( 9 kg ) ( 5 m / s )
A hockey puck with a mass of 0.12 kg is traveling across the ice at a velocity of 150 m/s downfield. What is the momentum of the hockey puck?(1 point)
Responses
P=18 N
P = 18 N
M=18 kg*m/s
M = 18 kg * m / s
P=18 kg*m/s
P = 18 kg * m / s
P=8*10−4 kg*m/s
The momentum of an object can be calculated as the product of its mass and velocity. Given that the mass of the hockey puck is 0.12 kg and its velocity is 150 m/s downfield, we can calculate its momentum as follows:
Momentum (P) = mass (m) × velocity (v)
= 0.12 kg × 150 m/s
= 18 kg·m/s
Therefore, the momentum of the hockey puck is 18 kg·m/s.