Final Answer:
The constant speed at the start of the acceleration is approximately 13 m/s.
Step-by-step explanation:
To determine the constant speed at the start of the acceleration, we can use the formula vₑ = vᵢ + at, where vₑ is the final velocity, vᵢ is the initial velocity, a is the acceleration, and t is the time. Since the motorcycle is moving at a constant speed, the acceleration is zero (a = 0). Therefore, the equation simplifies to vₑ = vᵢ. Given that the final velocity vₑ is 49 m/s and the time t is 12 seconds, the constant speed at the start (vᵢ) is also 49 m/s.
Now, to find the force applied (F), we use Newton's second law: F = ma, where m is the mass and a is the acceleration. Rearranging the formula to find a, we get a = F/m. Substituting the given values (F = 975 N and m = 325 kg), we find a = 3 m/s².
Now, we can use this acceleration in the original formula vₑ = vᵢ + at to find the constant speed at the start (vᵢ). Rearranging the formula, we get vᵢ = vₑ - at, and substituting the values, we find vᵢ = 49 - (3 × 12) = 13 m/s.
In summary, the constant speed at the start of the acceleration is approximately 13 m/s.