QUESTIONS AND ANSWERS SURE A+
✔✔emergency steering to avoid a crash - ✔✔where to steer?
leaving the road
avoid braking until 20 mph on loose surface
keep one set of wheels on the road
stay on the shoulder
find an escape route
✔✔velocity - ✔✔the speed and direction of a moving object
✔✔Friction - ✔✔is the resistance to motion between two moving objects. Friction occurs
when two objects come in contact and rub together
tires on the road are most important friction
✔✔the amount of friction between the tires and the roadway depends upon many
factors - ✔✔tire size, thread, type and inflation
speed
road surface conditions
weather conditions
✔✔law of momentum - ✔✔momentum is measured as an objects mass, or weight,
times its velocity as momentum increases its hard to overcome the effects of inertia
✔✔the law of inertia - ✔✔A law formulated by Galileo that states that motion, not rest, is
the natural state of an object, and that an object continues in motion forever unless
stopped by some external force.
✔✔both inertial and momentum have an affect on velocity control how? - ✔✔increased
momentum equals greater required stopping distance
brakes work harder
, friction is increased and more heat is generated
with increased momentum, inertia is harder to overcome
changing direction is thereby made more difficult
✔✔centrifugal force - ✔✔caused by inertia which tends to make a rotating body move
away from the center of rotation. centrifugal force is caused by the tendency of all
bodies to continue to move in the direction they began.
tends to push a vehicle traveling around a curve away from the center of the radius
higher the speed higher the centrifugal force
the tight the curve the more effect the force will have
✔✔centripetal force - ✔✔the resistance offered to the vehicles movement toward the
outside of the curve. it creates a balance by gravity against centrifugal force on weight
of objects
✔✔emergency vehicle characteristics affect the impact of the physical forces on the
vehicle. these include - ✔✔total weight and weight distribution (center of gravity) of the
vehicle
suspension system
braking system
baffling system (carry water)
✔✔total weight - ✔✔total weight of the vehicle has a drastic impact on the influence of
physical forces on the vehicle
total weight of vehicle with personnel and equipment
weight distribution between the front and rear axles also has a direct impact on the
vehicles handling
✔✔vertical center of gravity - ✔✔a vehicle with higher center of gravity is more likely to
weight shifting and roll over
✔✔two types of colission - ✔✔1- vehicle collision
first collision
vehicle vs another object
2- human collision
second collision
occupant vs safety system
-seatbelt
-air bags (supplemental restraint system)
unbelted occupant vs vehicle
occupant vs unsecured contents