Answer to Question #247076 in Physics for JaT

Question

1. Explain interms of impulse how padding reduces forces in a collision State this interms of a real example, such as the advantages of a carpeted vs. tile floor for a day care center.

2. Since astronauts in orbit are apparently weightless, a clever method of measuring their masses is needed to monitor their mass gains or losses to adjust diets. One way to do this is to exert a known force on an astronauts and measure the acceleration produced. Suppose a net external force of 50.0 N is exerted and the astronaut's acceleration measured to be 0.893 m/s, (a) calculate her mass with solution. (b) by exerting a force on the astronaut, the vehicle in which they orbit experiences an equal and opposite force. Discuss how this would affect the measurement of the astronaut's acceleration. Proposed a method in which recoil of the vehicle is avoided. Write your answers to the space provided below.

Answer 1

1. We know that

$$F=It.$$

The carpet is relatively thick, so, it decreases the time of impact. For the increased time of impact, the same force (of gravity) can be achieved by decreasing the impulse $I$, which corresponds to a smaller change in momentum and less severe injuries.

2. (a) The mass is

$$m=F/a=56\text{ kg}.$$

(b) The action of the force on the astronaut by the machine that is rigidly connected to the vehicle's body may reduce the measured acceleration. A method that avoids this is the momentum conservation as it can be done inside the vehicle's space without any rigid connections to its body.