suppose that a seat-belted mother riding in an automobile holds a 10 kg baby in her arms. the automobile crashes and decelerates from 50km/h to 0 in .1 s. what average force would the mother have to exert on the baby to hold it?? do you think she can do this?
To calculate the average force exerted by the mother on the baby, we can use Newton's second law of motion, which states that force (F) is equal to mass (m) multiplied by acceleration (a):
F = m * a
In this case, we need to determine the acceleration. We can use the equation for average acceleration:
a = (final velocity - initial velocity) / time
Given:
- Initial velocity (u) = 50 km/h = 50,000 m/3,600 s = 13.9 m/s
- Final velocity (v) = 0 m/s
- Time (t) = 0.1 s
Substituting these values, we can find the acceleration:
a = (0 - 13.9) / 0.1
a = -139 m/s²
Since the car is decelerating, the acceleration is negative.
Now, we can calculate the force exerted by the mother on the baby using the mass of the baby:
m = 10 kg
F = m * a
F = 10 kg * (-139 m/s²)
F = -1390 N
The negative sign indicates that the force is directed opposite to the motion of the car.
Therefore, the average force the mother would have to exert on the baby to hold it during the crash is 1390 Newtons (N). This force represents the force needed to overcome the inertia of the baby and keep it in place.
Regarding whether the mother can exert this force, it would depend on several factors such as her strength and the circumstances during the crash. It is advisable to always have babies securely restrained in appropriate car seats to minimize the risk of injury during accidents. Holding a baby in one's arms during a car crash can be extremely dangerous for both the mother and the baby.