Results 1 to 2 of 2

Thread: science- force mass and acceleration

  1. #1
    Junior Member
    Joined
    Dec 2007
    Posts
    41

    science- force mass and acceleration

    Hey guys please work this out for me showing me the steps and explaining it to me- science is so not my forte.

    g= 9.8m/s/s => this is what it says on top of the sheet. Do I really need it?
    Neglect friction. FIND THE FORCE REQUIRED.


    1) For a 50kg woman on a 20kg bicycle travelling at 6m/s to come to a halt in 2 seconds.

    2) To give a mass of 25 kgs. an acceleartion of 18m/s/s.

    3) To accelerate a 1500 kg space probe from 54 000 to 54900 kms/hr in 20 seconds.

    4) To increase the velocity of a 1 00 kg car from 10m/s to 20m/s in 5 seconds.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member SengNee's Avatar
    Joined
    Jan 2008
    From
    Pangkor Island, Perak, Malaysia.
    Posts
    155
    Quote Originally Posted by delicate_tears View Post
    Hey guys please work this out for me showing me the steps and explaining it to me- science is so not my forte.

    g= 9.8m/s/s => this is what it says on top of the sheet. Do I really need it?
    Neglect friction. FIND THE FORCE REQUIRED.


    1) For a 50kg woman on a 20kg bicycle travelling at 6m/s to come to a halt in 2 seconds.

    2) To give a mass of 25 kgs. an acceleartion of 18m/s/s.

    3) To accelerate a 1500 kg space probe from 54 000 to 54900 kms/hr in 20 seconds.

    4) To increase the velocity of a 1 00 kg car from 10m/s to 20m/s in 5 seconds.
    $\displaystyle F=ma$

    $\displaystyle F$ is the force required or net force.
    $\displaystyle m$ is the total mass.
    $\displaystyle a$ is the rate of change in velocity.


    1)

    $\displaystyle F=ma$
    $\displaystyle F=m\left(\frac{v-u}{t}\right)$
    $\displaystyle F=(50+70)\left[\frac{(0)-(6)}{(2)}\right]$
    $\displaystyle F=(120)(-3)$
    $\displaystyle F=-360N$

    2)

    $\displaystyle F=ma$
    $\displaystyle F=(25)(18)$
    $\displaystyle F=450N$

    3)

    $\displaystyle \Delta v$
    $\displaystyle =54900-54000$
    $\displaystyle =900 kmh^{-1}$
    $\displaystyle =\left(\frac{900\times 1000}{1\times 60\times 60}\right)ms^{-1}$
    $\displaystyle =250ms^{-1}$

    $\displaystyle F=ma$
    $\displaystyle F=m\left(\frac{\Delta v}{t}\right)$
    $\displaystyle F=(1500)\left(\frac{250}{20}\right)$
    $\displaystyle F=18750N$

    4)

    $\displaystyle F=ma$
    $\displaystyle F=m\left(\frac{v-u}{t}\right)$
    $\displaystyle F=(100)\left[\frac{(20)-(10)}{5}\right]$
    $\displaystyle F=200N$
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Force and acceleration question
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: Aug 12th 2010, 09:27 PM
  2. Replies: 21
    Last Post: Jul 26th 2010, 04:13 PM
  3. Mass under a force
    Posted in the Advanced Applied Math Forum
    Replies: 3
    Last Post: Aug 25th 2009, 12:31 PM
  4. acceleration and mass
    Posted in the Math Topics Forum
    Replies: 4
    Last Post: Jan 7th 2009, 03:11 AM
  5. Science: work and force
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: Mar 25th 2008, 12:52 AM

Search Tags


/mathhelpforum @mathhelpforum