Blake and Drew are playing horseshoes. Blake takes the first turn, and his horseshoe lands three-fourths of the way to the target. Drew takes the next turn, and his horseshoe lands past the target. Which statement best explains the results? (1 point)
A. Drew used a horseshoe with more mass and threw with the same force as Blake.
B. Drew used a horseshoe with more mass and threw with less force than Blake.
C. The horseshoes have the same mass, but Drew threw with less force than Blake.
D. The horseshoes have the same mass, but Drew threw with more force than Blake.
C. The horseshoes have the same mass, but Drew threw with less force than Blake.
Four movers pick up boxes. Each box has a different mass, and each mover applies a different amount of force to lift the box. Which box will have the greatest acceleration? (1 point)
A. a 20 kg box lifted with 40 N of force
B. a 10 kg box lifted with 40 N of force
C. a 20 kg box lifted with 60 N of force
D. a 10 kg box lifted with 60 N of force
The acceleration of an object is determined by the net force acting on it divided by its mass. Therefore, to find the box with the greatest acceleration, we need to find the combination of a high net force and a low mass.
A. a 20 kg box lifted with 40 N of force: acceleration = 40 N / 20 kg = 2 m/s^2
B. a 10 kg box lifted with 40 N of force: acceleration = 40 N / 10 kg = 4 m/s^2
C. a 20 kg box lifted with 60 N of force: acceleration = 60 N / 20 kg = 3 m/s^2
D. a 10 kg box lifted with 60 N of force: acceleration = 60 N / 10 kg = 6 m/s^2
From the calculations above, we can see that the box with the greatest acceleration is option D. a 10 kg box lifted with 60 N of force.
A baseball has a mass of 145 g. A pitcher throws the baseball so that it accelerates at a rate of 80 m/s?. How much force did the pitcher apply to the baseball? (1 point)
A. 65 N
B. 0.6 N
C. 1.8 N
D. 11.6 N
To find the force applied to the baseball, we can use Newton's second law of motion, which states that force (F) equals mass (m) multiplied by acceleration (a): F = m * a.
First, we need to convert the mass of the baseball from grams to kilograms by dividing by 1000:
m = 145 g / 1000 = 0.145 kg
Now we can calculate the force applied to the baseball using the given acceleration of 80 m/s?:
F = 0.145 kg * 80 m/s? = 11.6 N
Therefore, the pitcher applied a force of 11.6 N to the baseball, which is option D.
Which situation describes a negative acceleration? (1 point)
A. a bicycle increasing its velocity as the rider pedals harder
B. a swimmer moving at a constant velocity
C. a diver jumping off a diving board and falling to the swimming pool below
D. a runner slowing down at the end of a race