Physics questions! CALCULATING SPEED/VELOCITY/ACCELERATION...

Need some guidance on some Physics questions, I just started learning it in class so its a little confusing.

1.) The table (list) below includes data for a ball rolling down a hill. Fill in the missing data values in the table and determine the acceleration of the rolling ball.

TIME (SECONDS): 0 (START), 2, (MISSING), (MISSING), 8, 10.
SPEED (KM/H: 0 (START), 3, 6, 9, (MISSING), (MISSING), 15.

2.) A cart rolling down an incline for 5.0 seconds has an acceleration of 4.0 m/s (squared). If the cart has a beginning speed of 2.0m/s, what is its final speed?

3.) A helicopter's speed increases from 25m/s to 60m/s in 5 seconds. What is the acceleration of the helicopter?

4.) A motorcycle traveling at 25m/s accelerates at a rate of 7.0m/s (squared) for 6.0 seconds. What is the final speed of the motorcycle?

5.) A car staring from rest accelerates at a rate of 8.0m/s/s. What is its final speed at the end of 4.0 seconds?

6.) After traveling for 6 seconds a runner reaches a speed of 10m/s. What is the runners acceleration?

7.) A cyclist accelerates at a rate of 7.0m/s (squared). How long will it take the cyclist to reach a speed of 18m/s.

13.) A skateboarder traveling at 7 meters per second rolls to a stop at the top of a ramp in 3 seconds. What is the skateboarders acceleration?

I get confused with these types of ones because I cant use the triangle formula for speed distance and time with it.
( A = V - U / T).. and the rest.

Could you explain how you worked it out too please. Also how do I do a question where I get two different scales such as:

1.) ...they drive 30km in 15 minutes. What was their average speed in KM/H?

2.) 2000 meters in 900 seconds. What is the average speed in km/h?

3.) ...fly a balloon around the Earth in 80 days, taking the radius of the Earth to be 6400km calculate the average speed in m/s?

How do I do these as it makes me convert the values, and I don't even know how to calculate it in the first place?

- Any useful websites for this or anything - would be useful- THANKS :smile:

Reply 1

Nirgilis

Moved to physics help for you :h:

Reply 2

Jovious6638

Thanks

Posted from TSR Mobile

Reply 3

Stonebridge

No one is going to do these questions for you.

They are all (1 - 13) so called SUVAT questions

They are based on uniform acceleration and involve

acceleration a
initial velocity u
final velocity v
distance travelled s
time taken t

There are some equations that you use, one of them is v = u + at, there are two or three more, and you just plug the numbers in to get the answer.

Do you know these equations?
If not I suggest you wait until you have studied them.
If you have then I suggest you try them by plugging in the numbers and if you can't do them tell us where you are stuck.

Question 2
2.) A cart rolling down an incline for 5.0 seconds has an acceleration of 4.0 m/s (squared). If the cart has a beginning speed of 2.0m/s, what is its final speed?

You are given t, a and u

What is v?

Use the equation above.

Now try the rest yourself.

(edited 10 years ago)

Reply 4

TF1000

For the conversion question, you literally just convert to the units required then apply the required formula. 60 minutes in an hour, 1000m in a km, etc.

If he does 30km in 0.25 hours, then his average speed in km/h is 30x4.

If asked for metres per second from days and kilometres, then just calculate the values (seconds and metres) you need.

Etc

(edited 10 years ago)