A block slides down a frictionless inclined ramp and experiences no significant air resistance. If the ramp angle is 17 degrees above the horizontal and the length of the surface of the ramp is 20.0 m find the speed of the block as it reaches the bottom of the ramp assuming that it started from rest.

Respuesta :

Answer:

10.71m/s

Explanation:

Mechanical energy is conserved since the ramp surface had no friction and the experiences no significant air resistance

Potential energy at the top of the ramp = mgh

where m is m, g = 9.8 m/s² ( acceleration due to gravity ) and h is height

since the length of the surface L of the ramp is 20.0 m and it is inclined at 17°

h, height = Lsinθ = 20 sin 17° = 5.85 m

kinetic energy of the block = [tex]\frac{1}{2}[/tex]mv²

potential energy = kinetic energy

m × 9.8 × 5.85 m = [tex]\frac{1}{2}[/tex]mv²

cancel m on both side

v = √(2 × 9.8 × 5.85) = 10.71m/s

The speed of the block as it reaches the bottom of the ramp will be 10.71m/s.

What is speed ?

Speed is defined as the rate of change of the distance or the height attained. it is a time-based quantity. it is denoted by u for the initial speed while v for the final speed. its si unit is m/sec.

The given data in the problem is;

[tex]\rm \theta[/tex] is the ramp angle = 17⁰.

L is the length of the surface of the ramp i=20.0 m

v is the  speed of the block =?

Because the ramp surface has little friction and there is no considerable air resistance, mechanical energy is saved.At the top of the ramp, there is a lot of potential energy.

PE = mgh

From the trignometry the length is found as;

h= Lsinθ

h= 20 sin 17°

h= 5.85 m

The kinetic energy of the block is found as;

[tex]\rm KE = \frac{1}{2} mv^2[/tex]

From the law of conservation of energy the kinetic energy is equal to the potential energy;

[tex]\rm mgh= \frac{1}{2} mv^2[/tex]

[tex]\rm v= \sqrt{2gh} \\\\ \rm v= \sqrt{2\times 9.81 \times 5.85 } \\\\ \rm v= 10.71 \ m/sec[/tex]

Hence the speed of the block as it reaches the bottom of the ramp will be 10.71m/s.

To learn more about the speed refer to the link;

https://brainly.com/question/7359669