Thursday

March 5, 2015

March 5, 2015

Posted by **Amm** on Wednesday, December 1, 2010 at 7:26pm.

I know average speed= total distance/total time, but I am given an initial speed, an angle and delta x.

Mark throws a ball to Daniel with an initial speed of 20 m/s at an angle of 45 degrees. If they are initially 55 m apart, calculate the average speed Daniel has to run to catch the ball.

the answer is: 4.9 m/s

but how would I go about solving this?? Help, I'm stuck.

- Physics- HELP -
**bobpursley**, Wednesday, December 1, 2010 at 7:29pmUse the vertical component to find time in air.

Hf=hi+Viy*t-1/2 g t^2

0=0=20sin45*t-4.9t^2

t(20sin45-4.9t)=0

t= 20sin45/4.9 and that is time in air.

avg velocity= horizontal distance/time

= 55m/t

**Answer this Question**

**Related Questions**

Physics - 1. A person runs 800. m at an average speed of 6.00 m/s and then the ...

Maths - A boy cycled from his home to a friend's house 24km away at an average ...

Physics - In laboratory situations, a projectile’s range can be used to ...

Science..help plz... - Can you define speed, motion, constant speed and average ...

physics - why is the total distance traveled by a mass traveling in a circle of ...

physics - why is the total distance traveled by a mass traveling in a circle of ...

Class 11th Physics - My question is that, I read about Instantaneous Speed "...

Physics - 1. A person runs 800. m at an average speed of 6.00 m/s and then the ...

physics - A body at rest is given an initial uniform acceleration of 8m/s2 for ...

Physics - A. Consider the motion of a projectile. It is fired at t= 0. Its ...