Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Noob69 Needs Help! (Year 7)

  1. Mar 7, 2007 #1
    1)An aeroplane's mass will decrease during a flight as it uses fuel in its engine.

    Which statement describes the speed of the aeroplane during flight if the force from the engine remains constant?

    A) The speed will increase.
    B) The speed will decrease
    C) The speed will remain constant
    D) The Speed will decrease, then increase.
    (I think its B)
    2)Two spring balances, X and Y, each have a mass of 200 grams.

    A mass of 100 grams is attached to spring balance Y. Spring balance Y with the 100-gram mass is then connected to spring balance X.

    What would be the reading on each spring balance in the connected springs?

    A) X is 200g & Y is 100g
    B) X is 300g & Y is 100g
    C) X is 300g & Y is 300g
    D) X is 500g & Y is 300g
    (I think its A)
    3) Two cars taking part in a race are lined up at the starting line. Car Y = 800kg & Car X = 1000kg

    When the starter begins the race, the forces supplied to both cars are equal.
    What is the best way to describe the acceleration of each car.

    A) Car Y should accelerate more.
    B) Car X should accelerate more.
    C) Both cars should eccelerate equally because they start at the same time.
    D) Both cars should acceletate equally because they both have the same force.
    (I think its A)
    4)An identical satellite is orbiting Mars. Both satellites are the same distance from the centre of the planet that they orbit. Mars has a mass that is approximately 10% of Earth's mass.

    Which statement is correctly compares the force of gravity on the two satellites.

    A) The force on Satellite 2 is equal to the force on Satellite 1.
    B) The force on Satellite 2 is larger than the force on Satellite 1.
    C) There is no force on Satellite 2 but a large force on Satellite 1.
    D) The force on Satellite 2 is smaller than the force on Satellite 1.
    (No idea)
    5) Which statement about mass and weight is correct?

    A) Your mass would be the same on Earth and Mars.
    B) Your weight would be the same on Earth and Mars.
    C) Your mass would be less on Mars than on Earth.
    D) Your weight would be more on Mars than on Earth.

    (No idea)

    6) Four students investigated wheter plants need light to survive. They each set up identical plants in different conditions.

    Jake: All plants in the dark all the time.
    Kim: All plants in normal daylight
    Mitchell: Half the plants in the dark all the time. Half the plants in normal daylight.
    Ruby: Half the plants in normal daylight. Half the plants in artificial light.

    Which student has used a suitable control?

    (I think Mitchell does)

    Thank you. =D
    Last edited: Mar 7, 2007
  2. jcsd
  3. Mar 7, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    We do not do homework for you, so we need to see your thoughts on these questions.
  4. Mar 7, 2007 #3
    Oh, ok. But... i don't have any thoughts cause i don't get the question, thats why i need help. So, could you guys PLEASE help me?
  5. Mar 7, 2007 #4
    we are here to help anyone who needs it and makes an effort; but if you can't at least venture a guess on Question 1, this is probably not the right place in which to invest the effort of presenting problems, etc
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook