Answer:D
Explanation: i found the answer in an answer key!
Answer:
<h2>
E = 2.8028*10⁻¹⁹ Joules</h2>
Explanation:
The minimum energy needed to eject electrons from a metal with a threshold frequency fo is expressed as E = hfo
h = planck's constant
fo = threshold frequency
Given the threshold frequency fo = 4.23×10¹⁴ s⁻¹
h = 6.626× 10⁻³⁴ m² kg / s
Substituting this value into the formula to get the energy E
E = 4.23×10¹⁴ * 6.626 × 10⁻³⁴
E = 28.028*10¹⁴⁻³⁴
E = 28.028*10⁻²⁰
E = 2.8028*10⁻¹⁹ Joules
Answer:
Spring potential energy = 7.875Nm
Explanation:
<u>Given the following data;</u>
Extension, e = 15cm to meters = 15/100 = 0.15m
Spring constant, k = 350n/m
To find the force;
Force = spring constant * extension
Force = 350 * 0.15
Force = 52.5 Newton.
Now to find the spring potential energy we would use the formula below;
Spring potential energy = force * extension
Substituting into the equation, we have;
Spring potential energy = 52.5 * 0.15
<em>Spring potential energy = 7.875Nm</em>
Answer:
If an object moves in the opposite direction of a conservative net force, the potential energy will increase; and if the speed (not the velocity) of the object changes, the kinetic energy of the object also changes.
Explanation:
Hope i explained that clearly... :)