A 79.4 kg bobsled is pushed along a horizontal
surface by two athletes. After the bobsled is
pushed a distance of 7.1 starting from rest, its
speed is 4.7 m/s.
Find the magnitude of the net force on the
bobsled.
Answer in units of N.
To find the magnitude of the net force on the bobsled, we'll use Newton's second law of motion, which states that the force (F) acting on an object is equal to its mass (m) multiplied by its acceleration (a): F = m * a.
In this case, we're given the mass of the bobsled (m = 79.4 kg) and its initial and final velocities. Since the bobsled starts from rest, its initial velocity (u) is 0 m/s, and its final velocity (v) is 4.7 m/s. We're also given the distance (s) it travels, which is 7.1 m.
To calculate the acceleration of the bobsled, we can use the formula:
a = (v² - u²) / (2 * s).
Plugging in the given values:
a = (4.7² - 0²) / (2 * 7.1)
a = (22.09) / (14.2)
a ≈ 1.554 m/s²
Now that we have the acceleration, we can find the net force using Newton's second law. Rearranging the formula, we get:
F = m * a.
Plugging in the values:
F = 79.4 kg * 1.554 m/s²
F ≈ 123.33 N.
Therefore, the magnitude of the net force on the bobsled is approximately 123.33 N.