To analyze the relationship between mass and acceleration in your experiment, let's start by recalling Newton's second law of motion, which states that \( F = ma \), where \( F \) is the net force, \( m \) is the mass, and \( a \) is the acceleration. In this experiment, the force acting on the car (M1) is due to the gravitational force exerted by the mass (M2) connected to it via a string.
For simplicity, we can represent the forces in your system as follows:
- The gravitational force acting on mass \( M2 \) is \( F_{gravity} = M2 \cdot g \), where \( g \) is the acceleration due to gravity.
- The net force acting on the entire system (both M1 and M2) will influence the acceleration of M1.
Case 1: Doubling the mass of M1 (M1 to 2M1)
- When the mass of M1 is doubled, the new mass of M1 is \( 2M1 \).
- The total mass in the system now involves both \( 2M1 \) and \( M2 \), giving a total mass of \( 2M1 + M2 \).
- The gravitational force acting on \( M2 \) remains \( M2 \cdot g \).
- According to Newton's second law, the acceleration \( a \) can be expressed as: \[ a = \frac{F_{gravity}}{total ; mass} = \frac{M2 \cdot g}{2M1 + M2} \]
- Doubling the mass of M1 will decrease the acceleration of M1 because the total mass in the denominator has increased.
Case 2: Doubling the mass of M2 (M2 to 2M2)
- Here, the gravitational force acting on the mass now becomes \( 2M2 \cdot g \).
- The total mass of the system will thus be \( M1 + 2M2 \).
- The acceleration \( a \) can now be expressed as: \[ a = \frac{2M2 \cdot g}{M1 + 2M2} \]
- If \( M2 \) is doubled, the total force acting on the system increases, which would result in an increase in acceleration. Thus, the acceleration of M1 will increase in this case.
Case 3: Doubling both the masses of M1 and M2 (M1 to 2M1 and M2 to 2M2)
- In this case, the new values are \( 2M1 \) and \( 2M2 \).
- The gravitational force acting on the mass is now \( 2M2 \cdot g = 2(2M2) \cdot g = 4M2 \cdot g \).
- The total mass in the system becomes \( 2M1 + 2M2 \).
- The acceleration \( a \) will then be: \[ a = \frac{4M2 \cdot g}{2M1 + 2M2} = \frac{4M2 \cdot g}{2(M1 + M2)} = \frac{2M2 \cdot g}{M1 + M2} \]
- The overall effect here is that the acceleration of M1 remains the same as it was originally since both \( M1 \) and \( M2 \) were scaled by the same factor (2) which cancels out.
Summary:
- When mass of M1 is doubled: Acceleration of M1 decreases.
- When mass of M2 is doubled: Acceleration of M1 increases.
- When both masses M1 and M2 are doubled: Acceleration of M1 remains the same.
This illustrates the crucial interplay between mass and acceleration in a controlled system under the influence of gravity, in accordance with Newton's laws of motion.