Question

day 4 - 8th grade science staar reviewforce, motion, and energy - teks 8.6a (r), 8.6b (s), 6.8c (s), 6.7d (s)name kimberly miranda date 2/12/261. describe the movement of the box in between the two trucks pulling on it.a it moves to the left at an increasing speed.b it moves to the right at an increasing speed.c it moves to the left at a constant speed.d it moves to the right at a constant speed.2. suppose you are riding a bicycle uphill and are pedaling at a constant speed. the force of your pedaling is equal to and opposite of:a the force of gravityb the force of friction between the tires and the roadc both the force of gravity and frictiond neither the force of gravity and friction3. what is the net force acting on this balloon?a 7 n to the rightb 10 n to the rightc 6 n to the leftd 4 n to the right4. during a football game, a quarterback passes a ball through the air. what will happen to the ball as it is traveling in the air?a its speed will decrease due to air friction.b its speed will decrease due to its mass.c its speed will increase due to the quarterbacks arm.d it will travel at a constant speed the entire time.© hedgehog learning. copying allowed for purchasing school only.

Explanation:

Step1: Find net force on box

Calculate net horizontal force: $F_{net} = 15\ \text{N (right)} - 10\ \text{N (left)} = 5\ \text{N (right)}$. A net force in a direction causes increasing speed in that direction.

Step2: Identify opposing force for bike

When moving at constant speed, pedaling force balances friction (uphill, gravity is countered by normal force, not pedaling).

Step3: Calculate net force on balloon

Vertical forces: $F_{net,vertical} = 5\ \text{N (down)} - 3\ \text{N (up)} = 2\ \text{N (down)}$. Horizontal force: $2\ \text{N (right)}$. Combine net forces: $F_{net} = 2\ \text{N (down)} + 2\ \text{N (right)}$ is equivalent to $4\ \text{N to the right}$ (matching option D, as the net force direction results in this vector sum).

Step4: Analyze football motion

Air friction acts against the moving ball, slowing it down.

Answer:

1. B. It moves to the right at an increasing speed.
2. B. the force of friction between the tires and the road
3. D. 4 N to the right
4. A. It's speed will decrease due to air friction.