Answered

In a scene in an action movie, a stuntman jumps from the top of one
building to the top of another building 4.0 m away. After a running start,
he leaps at a velocity of 5.0 m/s at an angle of 15° with respect to the flat
roof. Will he make it to the other roof, which is 2.5 m lower than the
building he jumps from? ...?

Answer :

Yes, the stuntman can jump from one building to the other building.

Further explanation:

The stuntman jump from one building inclined at some angle to the other traversing a parabolic path.

Given:

The velocity of stuntman is 5m/s.

The distance between the buildings is 4m.

The difference in the height of the buildings is 2.5m.

The angle of inclination is [tex]{15^ \circ }[/tex].

Concept used:

When stuntman jumps from the top of one building to the top of other building he start running first then he jump at a velocity of 5m/s inclined at an angle of [tex]{15^ \circ }[/tex] from the horizontal of first building.

The velocity of stuntman has two components [tex]{v_x}[/tex] and [tex]{v_y}[/tex], respectively in the X-direction and in the Y-direction.

The expression for the distance in horizontal direction is given as.

[tex]x = \left( {v\cos \theta } \right)t[/tex]

 

Rearrange the above expression for time.

[tex]t = \dfrac{x}{{\left( {v\cos \theta } \right)}}[/tex]                             …… (1)

Here, t is the time of flight, v is the velocity of object and [tex]\theta[/tex]  is the angle of inclination.

The expression for the distance in Y-direction is given by the second equation of motion.

[tex]y = ut + \frac{1}{2}\left( { - g} \right){t^2}[/tex]                        

Here, u is the velocity in Y-direction and (–g) is the acceleration due to gravity directed in the downward direction.

The expression for the component of velocity in Y-direction is given as.

[tex]u = v\sin \theta[/tex]

 

Substitute [tex]v\sin\theta[/tex] for u in the above expression.

[tex]y = \left( {v\sin \theta } \right)t + \frac{1}{2}\left( { - g} \right){t^2}[/tex]                       …… (2)

Substitute 5m/s for v, 4m for x and [tex]{15^ \circ }[/tex] for   in equation (1).

[tex]\begin{aligned}t&=\frac{{4\,{\text{m}}}}{{\left({\left( {5\,{\text{m/s}}}\right)\left( {\cos {{15}^ \circ }}\right)}\right)}}\\&=0.828\,{\text{s}}\\\end{aligned}[/tex]

 

Substitute [tex]0.828\,{\text{s}}[/tex] for t, 5m/s for v, [tex]9.8\,{\text{m/}}{{\text{s}}^{\text{2}}}[/tex] for g and [tex]{15^ \circ }[/tex] for [tex]\theta[/tex] in equation (2).

[tex]\begin{aligned}y&=\left( {\left( {5\,{\text{m/s}}} \right)\sin \left( {{{15}^ \circ }} \right)} \right)\left( {0.828\,{\text{s}}} \right) + \frac{1}{2}\left( { - 9.8\,{\text{m/}}{{\text{s}}^{\text{2}}}} \right){\left( {0.828\,{\text{s}}} \right)^2}\\&=1.071 - 3.36 \\&=- 2.29\,{\text{m}}\\\end{aligned}[/tex]

 

Thus, the stuntman can jump from one building to another because its vertical distance is less than the difference in height of buildings.

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2.  Projection of ball https://brainly.com/question/11023695.

3. Conservation of momentum https://brainly.com/question/9484203.

Answer Details:

Grade: High School

Subject: Physics

Chapter: Kinematics

Keywords:

Force, motion, parabolic path, acceleration due to gravity, time of flight, angle of inclination, inclined plane, buildings, height difference, cliff, horizontal direction, vertical direction, 2.29 m, 2.3m, 0.828sec.

${teks-lihat-gambar} Nudrat

To know whether he will make it to the other roof that is 2.5m lower, we can say that;

He will make it to the other roof safely because the height he jumped which is 2.3 m is lesser than the roof height of 2.5 m from where he jumped.

We are given;

Velocity; v = 5 m/s

Distance jumped from the top of one building to the top of another building; x = 4 m

Angle made with respect to flat roof; θ = 15°

The formula for the horizontal distance is;

x = t(v cos θ)

Let us find the time taken;

t = x/(v cos θ)

Plugging in the relevant values gives;

t = 4/(5 cos 15)

t = 0.83 seconds

Now, to find the height we will use newtons equation of motion;

y = vt sin θ - ¹/₂gt²

Plugging in the relevant values gives;

y = (5 × 0.83 × sin 15) - ¹/₂(9.8 × 0.83²)

y = 1.074 - 3.376

y ≈ -2.3 m

This height is less than 2.5 m and as such we will conclude that he will make it to the other roof safely.

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