Formulas
A car can accelerate from rest to 27m/s in 9 seconds. Find the car's acceleration.
acceleration = final speed - initial speed / time
so 27 - 0 / 9 = 3 m/s^2
What is stored energy based on an object’s position?
Potential Energy
Convert 8475 m to km
8.475 km
When reading through a word problem, what is the first thing that has to be done?
a. Write down the formula
b. Close text read
c. Show your work
d. Write a sentence
B
___ H2 + ___ N2 ___ NH3
3 H2 + N2 = 2 NH3
What net force is needed to accelerate a 50kg cart at 15 m/s?
force = mass x acceleration so 50 x 15 = 750 N
What is a particle with no charge called?
A Neutron
Convert 2.75 km to meters
2750 meters
How can you find the net force if two forces act in opposite directions?
a. Multiply
b. Add
c. Divide
d. Subtract
D
____ S8 + ___ O2 = ___ SO2
S8 + 8 O2 = 8 SO2
Which has more momentum: a 225kg dolphin swimming at 5m/s, or a 300kg manatee swimming at 1.5m/s? Show formula, all work and a sentence for full credit.
momentum = mass x velocity
momentum of the dolphin = 1125 kg x m/s
momentum of the manatee = 450 kg x m/s
The dolphin has more momentum
The destruction of metal is called what?
Corrosion
Convert 3.85 km to meters
3850 meters
What is it called when matter changes from a liquid to a gas?
a. Condensation
b. Freezing
c. Evaporation
d. Melting
C
_____ P4 + ____ O2 = ____ P2O5
P4 + 5 O2 = 2 P2O5
Your laundry basket weighs 35N and your room is 4m above you on the second floor. It takes you 8 seconds to carry the laundry basket up. What is your power? Show formula, all work and a sentence for full credit.
power = force x distance / time
power = 17.5 W
The energy an object has due to its motion is called what?
Kinetic Energy
Convert 785 cm to meters
7.85 meters
A mixture in which particles can be seen and easily separated by settling or filtration is called a
a. Colloid
b. Suspension
c. Solution
B
____H2O2 = ___ H2O + ___ O2
2 H2O2 = 2 H2O + O2
You do 30 Joules of work while using a hammer. The hammer does 25 Joules of work on a nail. What is the efficiency of the hammer? Round to the nearest whole percent.
Efficiency of the hammer is 83%
The rate at which velocity changes is called what?
Acceleration
Convert 2,896 meters to km
2.896 kilometers
If an atom gains an electron, it becomes a __________________ ion?
a. Charged
b. Covalent
c. Negative
d. Positive
C
____NO + ____O2 = ___NO2
2 NO + O2 = 2 NO2