hey guys, i was wondering who is good at science? The reason i am asking is because i got some 6 six questions from college, and i have some clue on how to do them? So here they are:(adsbygoogle = window.adsbygoogle || []).push({});

1. Use the equation of motion to calculate the speed and distance travelled by an object falling from rest under gravity after 3,6 and 9 seconds. Take g=10 meters per seconds squared.

2. A force of 20 N acts for 8 seconds on a mass of 60Kg. What is the (a) acceleration, (b) final speed, (c) average speed, (d) distance covered during the 8 seconds.

3. A force of 20 N is exerted on the handle of a door 0.6 meters from the hinge. If the force acts a right angles to the door, what is the moment it exerts?

4. Calculate the kinetic energy of a car of mass 1200Kg travelling at 25 m/s. If it brakes to rest at 40 meters, calculate the braking force.

5. How much heat is released by the combustion of 4Kg of petrol of calorific value 46 MJ/kg?

6. A sonar beam is radiated from a ship and an echo is received after 0.9 seconds. If the speed of sound in the water is 1400 m/s, how far away is the reflecting surface?

These are the questions i have been given for homework. So guys, please be gentle and if u can, can u also show all clear workings out. Thanks

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# Homework Help: Can u guys help me with these 6 problems?

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