Two water jets are emerging from a vessel at a height of 50 centimeters and 100 centimeters. If their horizontal velocities at the point of ejection are 1 meter/second and 0.5 meters/second respectively, calculate the ratio of their horizontal distances of impact.

A. 1:04 B. 1:234 C. 2:01 D. 1.41:1 E. 3:02

Respuesta :

Answer: The correct answer is option (D).

Explanation:

Vertical distance  of first water jet = [tex]y_1=50 cm[/tex]

Vertical distance of second water jet = [tex]y_2=100 cm[/tex]

Horizontal velocity of first water jet =[tex]u_y_ 1=1 m/s[/tex]

Horizontal velocity of second water jet = [tex]u_y_2=0.5 m/s[/tex]

Vertical distance of first water jet:

[tex]y_1=(u_y_1)t_1+\frac{1}{2}gt_1^2[/tex]

[tex]u_y_1=0,(u_y_1)t_1=0[/tex]

[tex]t_1=\sqrt{\frac{2y_1}{g}}[/tex]...(1)

Similarly, Vertical distance of second water jet:

[tex]y_2=(u_y_2)t_2+\frac{1}{2}gt_2^2[/tex]

[tex]u_y_2=0,(u_y_2)t_2=0[/tex]

[tex]t_2=\sqrt{\frac{2y_2}{g}}[/tex]...(2)

Horizontal distance of first water jet:

[tex]x_1=(u_x_1)t_1+\frac{1}{2}at_1^2[/tex]

There is no acceleration in horizontal direction.

[tex]a=0,at_1^2=0[/tex]

[tex]x_1=(u_y_1)t_1[/tex]...(3)

Horizontal distance of second water jet:

[tex]x_2=(u_x_2)t_2+\frac{1}{2}at_2^2[/tex]

[tex]a=0,at_2^2=0[/tex]

[tex]x_2=(u_x_2)t_2[/tex]...(4)

On dividing (3) and (4):

[tex]\frac{x_1}{x_2}=\frac{(u_y_1)t_1}{(u_y_2)t_2}[/tex]

[tex]\frac{x_1}{x_2}=\frac{u_y_1}{u_y_2}\times\frac{\sqrt{\frac{2y_1}{g}}}{\sqrt{\frac{2y_2}{g}}}}=\frac{u_y_1}{u_y_2}\sqrt{\frac{y_1}{y_2}}[/tex]

(from (1) and (2))

[tex]\frac{x_1}{x_2}=\frac{1 m/s}{0.5 m/s}\sqrt{\frac{50 cm}{100 cm}}=1.41:1[/tex]

Hence, the correct answer is option (D).