Kinematics
Kinematics is the science that studies _____.
Motion
The unit of measurement of force
Newton (N)
True or False: Friction is a force that never opposes motion.
False. It always opposes motion.
True or False: Like poles of a magnet repel, and opposite poles attract.
True
What are the SI units for velocity?
m/s
When various forces act on a body, it is possible to determine a _____.
Resultant Force
Gravity _____ with the mass of two bodies and _____ with the distance that separates these bodies.
increases, decreases
The area around a magnet
Magnetic field
What is the formula for acceleration?
a = (v final - v initial) / (time)
A type of body that does not deform under the action of a force
Rigid Body
What is the value of gravitational acceleration on Earth?
9.8 m/s^2
An atom that gains electrons acquires what type of charge?
Negative
Types of motions in which the velocity varies at a constant rate
Uniformly accelerated motions
What is the formula for Hooke's Law?
k (spring constant) = Force / Elongation
What is the speed of light?
300 000 km/s
Identify a situation in real life where static electricity occurs.
Examples: combing dry hair, hair nearing a television, touching a car
In an 800-metre race, we observe that world champion David Rudisha passes the 150 m mark after 18 s and 75 hundredths.
How fast is he running?
Velocity = 8 m/s
Determine the force needed to make a car with a mass of 1000 kg acquire an acceleration of 3 m/s^2.
F=ma=1000 kg x 3 m/s^2=
3000 N
What is the weight of a man with a mass of 80 kg on Earth?
748 N
We rub a ruler and a plastic case with wool, and a comb with hair. We observe that the ruler and the case repel each other when they are put together, whereas the comb and the case attract each other. What will happen if we put the ruler and the comb together?
If the ruler and the case repel each other it is because their electric charges have the same sign.
If the comb and its case attract each other it is because their electric charges have different signs.
Therefore, the ruler and the comb will attract each other, since they have charges of different signs.