Question

1. if net force doubles on an object, what happens to acceleration?

a) halves
b) doubles
c) quadruples
d) no change

1. a car accelerates from 10 m/s to 30 m/s in 4 s. what is acceleration?

a) 4 m/s^2
b) 5 m/s^2
c) 6 m/s^2
d) 8 m/s^2

1. a car accelerates from 10 m/s to 30 m/s in 4 s. what is displacement?

a) 40 m
b) 60 m
c) 80 m
d) 100 m

1. a 20 kg object is pulled with 100 n. what is acceleration?

a) 2 m/s^2
b) 4 m/s^2
c) 5 m/s^2
d) 10 m/s^2

1. which of the following is not a vector?

a) velocity
b) acceleration
c) displacement
d) speed

Explanation:

Question 15 (Acceleration Calculation)

Step1: Recall Acceleration Formula

Acceleration \( a = \frac{\Delta v}{\Delta t} \), where \( \Delta v = v_f - v_i \), \( v_f \) is final velocity, \( v_i \) is initial velocity, and \( \Delta t \) is time.

Step2: Identify Values

\( v_i = 10 \, \text{m/s} \), \( v_f = 30 \, \text{m/s} \), \( \Delta t = 4 \, \text{s} \).

Step3: Calculate \( \Delta v \)

\( \Delta v = 30 - 10 = 20 \, \text{m/s} \).

Step4: Calculate Acceleration

\( a = \frac{20}{4} = 5 \, \text{m/s}^2 \). Wait, but options have 5? Wait, maybe typo, but let's check again. Wait, maybe I miscalculated? Wait, 30 -10 is 20, divided by 4 is 5. But option c is 5 m/s²? Wait, the options: a 4, b 6, c 5, d 8? Wait, maybe the original problem's numbers? Wait, maybe the user's image has 10 to 30 in 4s. So 20/4=5. So answer is c? Wait, but let's proceed.

Question 16 (Wait, no, question 16? Wait, the user's image: question 16 is "A car accelerates from 10 m/s to 30 m/s in 4 s. What is acceleration?" So same as above. So steps:

Step1: Use Acceleration Formula

\( a = \frac{v_f - v_i}{t} \)

Step2: Substitute Values

\( v_f = 30 \, \text{m/s} \), \( v_i = 10 \, \text{m/s} \), \( t = 4 \, \text{s} \)
\( a = \frac{30 - 10}{4} = \frac{20}{4} = 5 \, \text{m/s}^2 \)

Step1: Recall Displacement Formula for Uniform Acceleration

Displacement \( s = v_i t + \frac{1}{2} a t^2 \), or alternatively, since acceleration is constant, we can use \( s = \frac{(v_i + v_f)}{2} \times t \) (average velocity times time).

Step2: Identify Values

\( v_i = 10 \, \text{m/s} \), \( v_f = 30 \, \text{m/s} \), \( t = 4 \, \text{s} \).

Step3: Calculate Average Velocity

Average velocity \( = \frac{10 + 30}{2} = 20 \, \text{m/s} \).

Step4: Calculate Displacement

\( s = 20 \times 4 = 80 \, \text{m} \). So answer is b? 80 m.

Question 18 (Acceleration with Force)

Answer:

c. 5 m/s² (assuming option c is 5 m/s²)

Question 17 (Displacement Calculation)