Mechanical energy is conserved in the presence of which of the following types of forces select all that apply. a) frictional b) magnetic c) electrostatic d) gravitational

c) electrostatic

d) gravitational

Explanation:

Mechanical energy remains constant (conserved) if only conservative forces act on the particles.  

In this sense, the following forces are conservative:  

-Gravitational  

-Elastic

-Electrostatic

While the Friction Force and the Magnetic Force are not conservative.  

According to this, mechanical energy is conserved in the presence of electrostatic and gravitational forces.

Therefore the correct options are C and D.

wavelegth as in spectrum red oygbiv

we're given that v₀ = 0 and a = 5.4 m/s². therefore, since v = at + v₀ for constant acceleration the equation for velocity is

after 28s,

m/s

which i would round to 150 m/s as my final answer