ENGINEERING MECHANICS DYNAMICS
COMPREHENSIVE EXAM SCRIPT VERIFIED
QUESTIONS AND SOLUTIONS GRADED
APLUS
●● What is coloumbs law
Answer: frictional force is proportional to normal force upto a certain
point
F = Us N
●● what is delta r
Answer: how far and in what direction the particle moved from start to
end
●● whats r
Answer: initial position vector
●● whats r'
Answer: final position vector
●● how to calculate average velocity
,Answer: change in position vector / change in time
●● what direction is positive for velocity
Answer: right
●● How do you calculate average speed
Answer: total distance/total time
●● how do you find instantaneous velocity
Answer: dr / dt
●● how do u find speed
Answer: ds / dt
●● whats average acceleration
Answer: v / t
●● Whats formula for instantaneous acceleration
Answer: dv / dt
●● how to know if velocity is positive
Answer: right is positive
, left is negative
●● when you differentiate position with time once what do u get vs
when u do it twice
Answer: once u get velocity
twice u get acceleration
●● What are the kinematic equations for constant acceleration
Answer: 1. v = v0 + (ac)(t)
2. s = s0 +v0 + 1/2(ac)(t^2)
3. v^2 = (v0)^2 + 2(ac)(s-s0)
ac = constant accleleration
●● what does it mean when the acceleration is constant
Answer: its only one number the whole time
COMPREHENSIVE EXAM SCRIPT VERIFIED
QUESTIONS AND SOLUTIONS GRADED
APLUS
●● What is coloumbs law
Answer: frictional force is proportional to normal force upto a certain
point
F = Us N
●● what is delta r
Answer: how far and in what direction the particle moved from start to
end
●● whats r
Answer: initial position vector
●● whats r'
Answer: final position vector
●● how to calculate average velocity
,Answer: change in position vector / change in time
●● what direction is positive for velocity
Answer: right
●● How do you calculate average speed
Answer: total distance/total time
●● how do you find instantaneous velocity
Answer: dr / dt
●● how do u find speed
Answer: ds / dt
●● whats average acceleration
Answer: v / t
●● Whats formula for instantaneous acceleration
Answer: dv / dt
●● how to know if velocity is positive
Answer: right is positive
, left is negative
●● when you differentiate position with time once what do u get vs
when u do it twice
Answer: once u get velocity
twice u get acceleration
●● What are the kinematic equations for constant acceleration
Answer: 1. v = v0 + (ac)(t)
2. s = s0 +v0 + 1/2(ac)(t^2)
3. v^2 = (v0)^2 + 2(ac)(s-s0)
ac = constant accleleration
●● what does it mean when the acceleration is constant
Answer: its only one number the whole time