Recent content by Mayzu

38.9 is the initial velocity of the ball. That's what I've done, but I'm stuck...

Homework Statement A cricketer fields the ball in the outfield, some 80 meters from the wicket keeper. The fielder needs to return the ball to the wicket keeper as quickly as possible. He can throw the ball with a speed of 140 km/hr. The cricket ball has a mass of 0.0168kg (e) The fielder...

Homework Statement http://imgur.com/ymNWTOV Image isn't working, here is the question: http://imgur.com/ymNWTOV Homework Equations F=ma Weight force=mg Frictional force=μkN The Attempt at a Solution So for part (a):[/B] Force on 10kg block=mg=10x9.8=98N This is equal to the tension force in...

Δx is deviation from equilibrium. How does it cancel? My equation is: KE(at equilibrium)=1/2*k*(delta)x^2+m*g*(delta)x so to account for the gravitational potential decreasing, 1/2*mv^2=1/2*k*(delta)x^2-m*g*(delta)x Given v=23 and m=81kg, 1/2mv^2=21424.5J so that gives: 2142.5=1/2*k*Δx-2mgΔx...

Sorry, this is my first post so I didn't know how much detail to show :oops: The total length is 30m (as it says in part (a)) I don't understand why you need a minus... But even if you do, it still gives me the wrong answer :/ My friend got the right answer by ignoring GPE, but I don't see how...

Yeah, I was told you can just say GPE is 0 at equilibrium because it's all relative... But it's not working What's the correct way to do it then?:cry:

Homework Statement (a) An 81 kg student is launched from a bridge by his best friends, some 50 metres above the river surface. Fortunately, he is attached to a 30 m bungee cord with a spring constant of 270 N/m. i) What is the equilibrium length of the bungee cord, including the force of...