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...
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.
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.
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...
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...
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.
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☉...