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ok thanks
2. ### Projectile motion - Finding velocity (not given time or angle)

yea got the equation now, solved it in the shower haha. Thanks for the reply
3. ### Projectile motion - Finding velocity (not given time or angle)

Homework Statement A baseball is hit so that it reaches a maximum height of 20.0m and travels 90.0m before hitting the ground. With what velocity is the ball hit? The Attempt at a Solution I'm confused, i went into trying to find the time but i couldn't without a given angle. I went to say...
4. ### Projectile motion

quadratic of t? doesn't the equation already cancel out t^2 leaving t as an individual component?
5. ### Projectile motion

im trying to use y = yo + vit + 0.5at^2 which simplifies to y = vit + 0.5at^2 which then for to i used t = 2(y-vi)/a = 2(25-34.6)/-9.8 t = 1.9s Not sure if that is the answer but that's the equation with all of its components in it that i'v found.
6. ### Projectile motion

Cant seem to find an equation that works well with the values i have. There's always a component which i don't have and can't find without time in the equations i have or vice versa to finding time.
7. ### Projectile motion

Homework Statement A ball is kicked at a velocity of 40.0 ms at 60 degrees above the horizontal/ a) When is the ball 25.0m above the ground? The Attempt at a Solution First i broke them down into there x and y components but having problems on the (25.0m) part. I did Vix = 40 cos 60 = 20...
8. ### Calculating minimum force

Thanks both of you for your replies Yes i forgot its actually the weight from the rock, thanks for reminding me
9. ### Calculating minimum force

1. A 1 tonne rock is being dragged up a 30 degree slope using the a pulley system. If there is a constant resistance to movement between the rock and the ground of 350N, calculate the minimum force necessary to drag the rock up the slope. 2. 3. All i got so far is 1t = 1000kg...
10. ### Solar Luminosity

Thanks guys, i found out that i put 7L☉/ 4π(11.41)₂ as a fraction in the calculator... -_- haha thank your very much for your help vbillej
11. ### Solar Luminosity

I just don't get what 7L☉ is, i looked up L☉ but i still don't really understand how the answer was 0.004 L☉. Like how would i put 7L☉ into a calculator.
12. ### Solar Luminosity

In a question is says that Brightness = Luminosity/4πr₂ (for a star). Procyon = 7L☉ and 11.41 light years as distance. the equation in B= 7L☉/ 4π(11.41)₂ the answer turned out to be 0.004 L☉ watts per square light year (its a textbook question). What i don't understand is what is 7L☉...