Download Practice Math Problems for chapter 6

Practice Math Problems for chapter 6
(You need to be able to do these WITHOUT looking at
the formula triangles and NO calculators)
1. If an object travels 10 m in 0.5 seconds. What was
the object’s speed?
Speed = distance ÷ time
Speed = 10 m ÷ 0.5 s
Speed = 20 m/s
2. If an object travels at 82 m/s how far will it travel in
5.3 seconds?
Distance = speed × time
Distance = 82 m/s × 5.3 s
Distance = 434.6 m
3. How long will it take an object to travel 65 m if it is
traveling at 4 m/s?
Time = distance ÷ speed
Time = 65 m ÷ 4 m/s
Time = 16.25 s
4. If car speeds up from 1.5 m/s to 6.4 m/s in 3 seconds,
find the acceleration.
Acceleration = (Velocityf - Velocityi) ÷ time
Acceleration = (6.4 m/s – 1.5 m/s) ÷ 3 s
Acceleration = (4.9 m/s) ÷ 3 s = 1.63 m/s2
5. An object is dropped. Ignoring air resistance how fast
is it moving at the end of 4 seconds?
∆Velocity = gravity x time
∆ velocity = velocityfinal – velocityinitial
Vf – Vi = gravity x time
Vf – 0 m/s = 9.8 m/s2 × 4 s
Vf = 39.2 m/s
6. If an object was dropped and is now moving at 29.4
m/s. How long was it falling for?
time = ∆Velocity ÷ gravity
∆ velocity = velocityfinal – velocityinitial
Time = (Vf – Vi) ÷ gravity
Time = (29.4 m/s – 0 m/s) ÷ 9.8 m/s
Time = 3 s
7. Find the force necessary to cause a 2.3 kg object to
accelerate at 7.2 m/s2.
Force = mass x acceleration
Force = 2.3 kg x 7.2 m/s2
Force = 16.56 N
8. If a 15 N force acts on a 4 kg object, what will the
objects acceleration be?
Acceleration = Force ÷ mass
A = 15 N ÷ 4 kg
A = 3.75 m/s2
9. If a 27 N force causes an object to accelerate at 40.5
m/s2, what was the object’s mass?
Mass = force ÷ acceleration
Mass = 27 N ÷ 40.5 m/s2
Mass = 0.67 kg
10. An object has 7 kg of mass and is moving 4 m/s.
Find momentum.
Momentum = mass x velocity
P=mxv
P = 7 kg x 4 m/s
P = 28 kg m/s
11. An object has 51 kg m/s of momentum. If the
mass is 17 kg find the velocity of the object.
Velocity = momentum ÷ mass
V=p÷m
V = 51 kg m/s ÷ 17
V = 3 m/s
12. An object has 92 kg m/s of momentum. If the
velocity of the object is 4 m/s. find the mass of the
object.
mass = momentum ÷ velocity
m=p÷v
m = 92 kg m/s ÷ 4
m = 23 kg
13.
Find the weight of a 50 kg object on earth.
Weight = mass x gravity
W=mxg
W = 50 kg x 9.8 m/s2
W = 490 N