I have added the question as an image. I don't understnad part (b) of the question.I tried it but got t=2(v0)/g with v0 the intial speed. the answer is: t = v0/gThanks in advance!

I have added the question as an image I dont understnad part b of the questionI tried it but got t2v0g with v0 the intial speed the answer is t v0gThanks in adv class=

Respuesta :

Given data

*The intial horizontal velocity of the potato is u_x = v_o

*The vertical acceleration of the potato is a_y = -g

*The given angle is 45 degree

(a)

The formula to calculate the horizontal co-ordinate of potato is given as

[tex]x=u_xt+\frac{1}{2}a_xt^2[/tex]

*Here a_x = 0 m/s^2 is the horizontal acceleration of the potato

Substitute the known values in the above expression as

[tex]\begin{gathered} x=v_0t+\frac{1}{2}(0)(t^2) \\ =v_0t \end{gathered}[/tex]

The formula to calculate the vertical co-ordinate of potato is given as

[tex]y=u_yt+\frac{1}{2}a_yt^2[/tex]

*Here u_y = 0 m/s is the initial vertical velocity of the potato

Substitute the known values in the above expression as

[tex]\begin{gathered} y=(0)(t)+\frac{1}{2}(-g)t^2 \\ =-\frac{1}{2}gt^2 \end{gathered}[/tex]

As from the given data, apply the condition as

[tex]\begin{gathered} x=y \\ v_0t=\frac{1}{2}gt^2 \\ t=\frac{2v_0}{g} \end{gathered}[/tex]

Hence, the equation for the time taken is t = 2v_0/g

The horizontal co-ordinate of potato is calculated as

[tex]\begin{gathered} x=v_0t \\ =v_0(\frac{2v_0}{g})_{} \\ =\frac{2v^2_0}{g} \end{gathered}[/tex]

The vertical coordinate of the potato is calculated as

[tex]\begin{gathered} y=-\frac{1}{2}gt^2 \\ =-\frac{1}{2}g(\frac{2v_0}{g})^2 \\ =-\frac{2v^2_0}{g} \end{gathered}[/tex]

Hence, the co-ordinate of the potato is (2v_0^2/g, -2v_0^2/g)

(b)

The formula to calculate the angle of position co-ordinates is given as

[tex]\tan \theta=\frac{y}{x}[/tex]

Substitute the known values in the above expression as

[tex]\begin{gathered} \tan 45^0=\frac{y}{x} \\ x=y \end{gathered}[/tex]

The above equation shows that time taken is the same for the angle and co-ordinate is also the same.

Thus, the equation for the time taken is the same as t = 2v_0/g, and the co-ordinate of the potato is the same as (2v_0^2/g, -2v_0^2/g)