midterm 1 Flashcards
Which of the following statements best represents Newton’s first law of motion?
Every object at rest, or in uniform motion, will remain in that state of motion unless compelled to do otherwise by forces acting upon it.
If an object is in uniform motion then the object will have a constant speed and direction.
True
Which of the following statements is true?
The mass of an object is always the same, but the weight of an object changes based on the acceleration of gravity acting on the object.
What are the units for distance, speed, and acceleration, respectively?
m, m/s, m/s2
If there were no air friction (a vacuum), and if a feather and a wrench were dropped from the same height at the same time they would hit the ground at different times.
False
What is the acceleration due to gravity of all objects on Earth?
9.8 m/s2,
32 feet/sec2,
22 miles/hour every second
If there was a green and red ball located at the same height. If the red ball was shot horizontally and the green ball was dropped which ball would hit the ground first?
Both balls would hit the ground at the same time
If a ball was thrown in the air, what is the acceleration of the ball the moment it reaches its maximum height and zero speed?
9.8 m/s2
What law of motion describes why it is easier to accelerate objects with little mass?
Newton’s 2nd law of motion
If someone was in outer space with no other objects nearby, and they threw a ball. What would happen to the ball?
The ball would go at the same speed and direction forever.
What would happen if you had two charges and you brought them close together?
The charges would attract one another if they were opposite charges and repel one another if they were the same charges.
All electric currents create magnetic fields.
true
Which of the following scientists came up with the idea for positive and negative charges?
Benjamin Franklin
What experiment was used to determine the charge of an electron?
Oil drop experiment
What type of electricity is used in our homes, and what type of electricity is used to charge our batteries? (Hint look up how cellphone chargers work)
Alternating current is used in our homes and direct current is used to charge our batteries.
A generator is a set of magnets turning inside coiled wires. As a turbine moves the generator the magnetic field changes within the coils causing an electric current or voltage.
true
A speaker is one example of an electromagnet.
true
If you were standing on a scale in a stopped elevator, what would happen to the your weight reading on the scale if the elevator started moving up?
Weight more than at rest