Transcript 2 m/s - Net Start Class

D
This is Newton’s 2nd law-- objects don’t change mass just because
they are on another planet, and since Force = mass X acceleration,
less force must mean slower acceleration.
C
• Speed is distance divided by time. The
total distance was 40 ft, the time was 8
seconds. 40 divided by 8 = 5
A
• Since they are pulling in different
directions, the forces are subtracted and
Joy wins by 20N.
C: Since they are both moving it up (same direction),
their forces are added together.
100 N + 150 N = 250 N
B: Speed is distance divided by time. 80 cm.
divided by 20 seconds is 4 cm/s
D: Newton’s first law
B: Balanced forces are equal forces, and cancel each other out
causing no motion. Net force is the overall forces acting on an
object, either added together if they are same direction or subtracted
if different directions.
B: If you continue the speed and extend the table of it
going another 5 meters each minute, it will reach 40
meters at 6 minutes.
D: This is Newton’s 2nd law-- Force = mass X acceleration. Gravity is the same
to everything everywhere on earth, but small things are light enough to be fast
and fight gravity, but people are big and heavy so we go too slow!
D: Gravity is the only force that pulls things DOWN, which is
what sinking is.
D:This is Newton’s 2nd law-- Force = mass X acceleration. Big and heavy things
have more force, so the lighter ball will have LESS (which is what the question asked
about!)
C: Speed = distance divided by time. 240 miles divided by 6 hours = 40 mph
B: This is Newton’s 2nd law-- Force = mass X acceleration.
10 N = 5 kg. X 2 m/s
20 N = 10 kg. X 2 m/s
They will have equal acceleration!
D: The forces are balanced, since they are in different directions and
equal. That means they cancel each other out and there is no motion.
Remember, lower means SLOWER! So the higher one went fastest,
because it travelled farther in the same amount of time.
B: This is Newton’s 1st law-- with no force to
stop him, the skateboarder’s inertia will keep him
moving forward (like not wearing a seatbelt in a
car).
D: This is Newton’s 2nd law-- Force = mass X acceleration. Something
heavy is not fast, because the force is used up on its heavy weight.
(Like how you can throw a ball much easier and faster than you could
throw a sofa!)
How long will it take Ryan to get to
the 10 cm mark?
20 seconds
What is the average speed?
50/25 = 2meters
cord
Spring
Which cart will accelerate faster when the cord is cut
and force is provided by the spring?
4 kg because it is lighter
• What is the speed at 7m?
• What is the speed at 8m?
About 6.3
About 5.9
• Teri hits a 4 kg baseball ball with a force of
8 N, and Sam hits a 2 kg ball with a force
of 4 N. Whose ball had the greater
acceleration?
• F= Mass X acceleration
8= 4*A
4= 2*A
8/4 = A
2 =A
4/2 = A
2=A
Object
Toy gun
Rifle
BB gun
Mass
40 g
5g
1g
Acceleration
5 m/s
100 m/s
1000 m/s
• Reagan collected the above data during his
experiment. Based on this data, which gun
would have the most force?
• F= Mass X acceleration
200 = 40 * 5 Toy gun
500 = 5 * 100 Rifle
1000 = 1 * 1000 BB GUN!!
The cart will move by a net force of
how many newtons?
200 – 150 = 50 N
What is the net force on the skateboarder?
35-35= 0
30 N
12 N
How much force is being applied to the boulder?
30-12 = 18 N