An object has a mechanical energy of 1575 J and a potential energy of 1265 J.

a.What is the kinetic energy of the object?

b.If the mass of the object is 12 kg, what is its speed?

c.How high above ground is the object?

7.A 5 kg object is moving downward at a speed of 12 m/s. If it is currently 2.6 m above the ground…

a.What is its kinetic energy?

b.What is its potential energy?

c.What is its mechanical energy?

Respuesta :

6.  

A. 1575 - 1265 = 310J

B.  KE 1/2 MV^2

   V=√2·KE/M = √2(310)/12   V = 7.2mls

C.  PE = 1265 = mgh

h= 1265/mg = 1265/(12)(92)    h= 10.8m    

7.  

A.  KE  = 1/2 mv^2  0.5(5)(12)^2    KE = 360J

B.  PE = mgh = (5)(9.8)(2.6)  PE = 127.4J

C.  ME = KE + PE = 360 + 127.4   ME = 487.4J

Kinetic energy is the energy of a body due to the virtue of its motion while potential energy is the energy of a body due to the virtue of its position.

1a) The formula for calculating the mechanical energy of an object is expressed as:

[tex]ME = PE + KE[/tex]

Given the following parameters

P.E = 1265Joules

M.E = 1575Joules

Substitute the given parameters into the formula;

[tex]K.E=M.E-P.E\\K.E=1575-1265\\K.E=310Joules[/tex]

The kinetic energy of the body is 310 Joules

b) The formula for calculating the kinetic energy is expressed as:

[tex]K.E=\frac{1}{2}mv^2\\310=\frac{1}{2}(12)v^2\\620=12v^2\\v^2=\frac{620}{12} \\v^2= 51.66\\v=7.19m/s[/tex]

Hence if the mass of the object is 12 kg, the speed will be 7.19m/s

c) The formula for calculating the potential energy is expressed as:

[tex]P.E=mgh\\1265=12(9.8)h\\h=\frac{1265}{117.6}\\h= 10.76m[/tex]

Hence the height of the object is 10.76m

2a) Given the following parameters

Mass = 5kg

Speed = 12m/s

Height = 2.6m

[tex]K.E=0.5mv^2\\K.E=0.5(5)(12)^2\\K.E=360Joules[/tex]

b) Get the potential energy

Potential Energy = mgh

Potential Energy = 5 * 9.8 * 2.6

Potential Energy = 127.4joules

c) Mechanical energy = P.E + K.E

Mechanical energy = 360 + 127.4

Mechanical energy = 487.4Joules

Hence the mechanical energy of the body is 487.4Joules

Learn more here: https://brainly.com/question/14509220