As a civil engineer for your city, you have been assigned to evaluate the purchase of spring-loaded guard rails to prevent cars from leaving the road. in response to a request for proposals*, one company states their guard rails are perfect for the job. each section of their guard rails consists of two springs, each having a force constant 3.13400 105 n/m with a maximimum distance of compression of 0.614 m. (according to the manufacturer, beyond this compression the spring loses most of its ability to absorb an impact elastically.) the largest vehicle the guardrails are expected to stop are trucks of mass 4550.000 kg. what is the maximum speed at which these guard rails alone can be expected to bring such vehicles to a halt within the stated maximum compression distance? (assume the vehicles can strike the guard rail head on and that the springs are perfectly elastic.)
m/s
given your result which section of road often features such a speed
school zone
large road
highway
guard rails are pointless if the acceleration they create seriously injures passengers. one important safety factor is the acceleration experienced by passengers during a collision. calculate the maximum acceleration of the vehicle during the time in which it is in contact with the guard rail.
m/s^2
if the highway department considers 20 g\'s the maximum safe acceleration, is this guard rail safe in regards to acceleration?

Follow these directions and answer the questions. 1. shine a pencil-thin beam of light on a mirror perpendicular to its surface. (if you don't have a laser light as suggested in the video, you can make a narrow beam from a flashlight by making a cone from black construction paper and taping it over the face of the flashlight.) how does the light reflect? how does the relationship of incident to reflected ray relate to the reflection of water waves moving perpendicular to a barrier? 2. shine a pencil-thin beam of light on a mirror standing on a sheet of paper on the table (or floor) so that you can mark the incident ray and reflected ray. (you can support the mirror from the back by taping it to a wooden block.) 3. mark a line on the paper representing the reflective surface. (the reflective surface of a mirror is usually the back edge.) 4. draw a dashed line perpendicular to the mirror surface at a point where the incident and reflected ray meet. this perpendicular is called a normal to the surface. 5. measure the angles between the rays and the normal. the angle of incidence is the angle formed by the incident ray and the normal to the surface. the angle formed by the reflected ray and normal is called the angle of reflection (r). what is the angle of incidence? what is the angle of reflection? 6. repeat for several different angles. (see report sheet for details.) what appears to be the relationship between the angle of incidence and angle of reflection? in science 1204, what was the relationship for these two angles made by the reflection of waves in a ripple tank? 7. roll a ball bearing so that it hits a fixed, hard surface (a metal plate) at several angles (including head-on). observe the way in which the ball bearing reflects. what generalization can you make about how a ball bearing reflects from a wall? have you proved that light can only behave like a wave?

Which object is most likely represented by a dot?

Agroup of students were investigating the force of gravity. they began by dropping a foam ball from a height of 3 meters into a bucket of sand. the ball hit the sand in 0.306 seconds. they dropped additional balls of approximately the same diameter, but of different masses. here is the data they collected. based on this experiment and the collected data, what would their conclusion be?