# PLC Activity #7 Practice Exam 1.1 ```PLC Activity #7
Practice Exam 1.1
All problems are worth 20 points
Problem 1
A car traveling 15.6 m/s is 24.0 m from a barrier when the driver slams on the brakes.
The car hits the barrier 2.00 s later.
a. What is the car’s constant deceleration before impact? Answer: −3.56 m/s2
b. How fast is the car traveling at impact? Answer: 8.43 m/s
Problem 2
Bond, James Bond, is escaping across a rooftop and runs off the roof horizontally at a
speed of 5.3 m/s, hoping to land on the roof of an adjacent building. The horizontal
distance between the two buildings is 12 feet, and the roof of the adjacent building is 2.0
m below the jumping-off point. Does James Bond make the jump? That is, is James
Bond able to land on the adjacent building? If not, by how much did he miss? (Hint: 1 ft
= 0.304 m) Answer: No, 10 inches
Problem 3
A student, crazed by the first physics Midterm, uses a pushing force of
80 N angled at 70&deg; to push a 5.0 kg book across the frictionless ceiling
of his room.
a. What is the block's acceleration? Answer: 5.5 m/s2
b. What is the force of the ceiling on the book? Answer: 26 N
Problem 4
A block of mass 5.00 kg is pulled along a horizontal frictionless floor by a cord that
exerts a force of 12.0 N at an angle of 250 above the horizontal.
a. What is the block's acceleration? (b) What is the force of the floor? Answer: 2.18 m/s2
b. What is the force of the floor? Answer: 43.9 N
Problem 5
Use short concise sentences to answer the following questions using physics principles.