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Lexan

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PLEEEEEEEEEEASE HELP THIS IS DUE TOMORROW AND I'M DESPERATE......

A golf ball with a mass of 150g is hit straight out from the edge of a 50m high cliff with a speed of 30ms-1 Ignoring air resistance, calculate

a. the time taken for the ball to reach the ground
b. the distance from the base of the cliff that it lands
c. it's velocity just prior to impact
d. the force on the ball half way through its time of flight.


a 50g bullet is fired at 550ms-1 at an angle of 60 degrees to the hirizontal ignore air resistance

a. what height does it reach
b. how long does it remaain airborne for
c. calculate it's range
d. determine it's velocity after 2s of flight
e. what is the maaximum kinetic energy the bullet possesses
 

Zozo6969

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[FONT=&quot]OK
[/FONT]
[FONT=&quot]
[/FONT]
[FONT=&quot]1a)v²=u²+2ar[/FONT]
[FONT=&quot]v²=0+2x9.8x50[/FONT]
[FONT=&quot]v²=980[/FONT]
[FONT=&quot]v=31.3 m/s[/FONT]
[FONT=&quot]v=u+at[/FONT]
[FONT=&quot]31.3=0+9.8t[/FONT]
[FONT=&quot]T=3.19s (do not x by 2 since it is only half a parabola)[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]b)r=ut[/FONT]
[FONT=&quot]r=30x3.19[/FONT]
[FONT=&quot]r=95.82m[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]c)By Pythagoras[/FONT]
[FONT=&quot]v²=30²+31.3²[/FONT]
[FONT=&quot]v=43.36 m/s[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]d)f=ma[/FONT]
[FONT=&quot]f=0.15x9.8[/FONT]
[FONT=&quot]f=1.47 N[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]2a)By Pythagoras[/FONT]
[FONT=&quot]Ux=550cos60[/FONT]
[FONT=&quot]Ux=275 m/s[/FONT]
[FONT=&quot]Uy=550sin60[/FONT]
[FONT=&quot]Uy=476.31 m/s[/FONT]
[FONT=&quot]v²=u²+2ar[/FONT]
[FONT=&quot]0=476.31²-2x9.8r[/FONT]
[FONT=&quot]19.6r=476.31²[/FONT]
[FONT=&quot]r=11575.06m[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]b)v=u+at[/FONT]
[FONT=&quot]0=476.31-9.8t[/FONT]
[FONT=&quot]9.8t=476.31[/FONT]
[FONT=&quot]T=48.6 s x2[/FONT]
[FONT=&quot]=97.21 s[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]c)r=Ux x t[/FONT]
[FONT=&quot]r=275x97.21[/FONT]
[FONT=&quot]r=26731.68 m[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]d)v=u+at[/FONT]
[FONT=&quot]v=476.31-9.8x2[/FONT]
[FONT=&quot]v=456.71 m/s[/FONT]
[FONT=&quot]By Pythagoras[/FONT]
[FONT=&quot]v²=456.71²+275²[/FONT]
[FONT=&quot]v=533.11 m/s[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]e)Ek=0.5mv²[/FONT]
[FONT=&quot]v is greatest at initial and final (use initial)[/FONT]
[FONT=&quot]Ek=0.5x0.05x550²[/FONT]
[FONT=&quot]Ek=7562.5 J[/FONT]


Think all of it is right
 

Lexan

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thankyou soooooooooo much! its helped a lot and most of the answers that you have given are exactly what i have
 

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