Here's what you need to memorize for your exam tomorrow.
Distance = (speed) x (time) .
That's it. Memorize it.
-- If the question wants you to find speed, use it exactly in that form.
-- If the question wants you to find speed, then divide each side by (time)
and it says
. Time = (distance) / (speed) .
-- If the question wants you to find time, then divide each side by speed,
and it says
. Time = (distance) / (speed) .
So if you memorize that one equation ... Distance = (speed) x (time) ...
you can solve ANY problem to find distance, speed, or time.
On the sheet in the picture . . . . .
#2). The question is "How long ?". That's TIME that you have to find.
Use the equation in the form of
. TIME = (distance) / (speed)
. = (60 km) / (48 km/h)
. = 1.25 hours .
#3). This one wants you to find SPEED. Use the equation in the form of
. SPEED = (distance) / (time)
but be careful. The time has to be in hours. 55 minutes = 55/60 of an hour.
. SPEED = (distance) / (time)
. = (60 km) / (55/60 hour)
. = (60 x 60 km) / (55 hour)
. = 65.45 km/hr .
#4). This one wants you to find TIME. (It says "How long ?".)
It's two trips, so you have to find the time for each trip.
First trip: TIME = (distance)/(speed) = (24 km)/(65 km/hr) = 0.369 hr
Second trip: TIME = (distance)/(speed) = (50 km)/(80 km/hr) = 0.625 hr
Total time for both trips = (0.369 hr) + (0.625 hr) = 0.994 hour
Answer:
The process by which the balloon is attracted and possibly sticks to the wall is known as static electricity which is the attraction or repulsion between electric charges which are not free to move.
The wall is an insulator.
Explanation:
When a balloon is blown and tied off, and then the balloon is rubbed on the woolly object once in one direction, and the side that was rubbed against the wool is brought near a wall and then released, it is observed that the balloon is attracted to and sticks to the wall. The above observation is due to static electricity.
Static electricity refers to electric charges that are not free to move or that are static. One of the means of generating such charges is by friction. When the balloon is rubbed on the woollen material, electrons are given away to the balloon's surface. Since the balloon is an insulator (materials which do not allow electricity to pass through them easily), the electrons are not free to move. When the balloon is brought near to a wall, there is a rearrangement of the charges present on the wall. Negative charges on the wall move farther away while the positive charges on the wall are attracted to the electrons on the balloon's surface. Because the wall is also an insulator, the charges are not discharged immediately. Therefore, this attraction between opposite charges as well as the static nature of the charges results in the balloon sticking to the wall.
The electromagnetic that has a shorter wavelength is ultraviolet (UV)
Answer:
Less than 1 m
Explanation:
When objects are getting closer to each other there is a slight change in the wavelength that is being transmitted by either objects. This is known as the blue shift of waves. Here, the wavelength reduces.
In the opposite case the when objects are getting farther from each other there is a slight change in the wavelength that is being transmitted by either objects. This is known as the red shift. Here, the wavelength increases.
In this case the spaceship is getting close to Earth hence the wavelength will be lower than 1 m.
F = ma
We have mass = 0.2kg
and acceleration = 20 m/s^2
So..
F = (0.2)(20)
F = 4 N
