Answer:
Her speed is 9.8 meter per second
Explanation:
Newton's second law states that acceleration (a) is related with force (F) by:
(1)
Here the only force acting on the firefighter is the weight F=mg so (1) is:
Solving for a:
Now with the acceleration we can use the Galileo's kinematic equation:
(2)
With Vf the final velocity, Vo the initial velocity and Δx the displacement, because the firefighter stars from rest Vo=0 so (2) is:
Solving for Vf
Answer:
The work flow required by the compressor = 100.67Kj/kg
Explanation:
The solution to this question is obtained from the energy balance where the initial and final specific internal energies and enthalpies are taken from A-17 table from the given temperatures using interpolation .
The work flow can be determined using the equation:
M1h1 + W = Mh2
U1 + P1alph1 + ◇U + Workflow = U2 + P2alpha2
Workflow = P2alpha2 - P1alpha1
Workflow = (h2 -U2) - (h1 - U1)
Workflow = ( 684.344 - 491.153) - ( 322.483 - 229.964)
Workflow = ( 193.191 - 92.519)Kj/kg
Workflow = 100.672Kj/kg
Answer:
b)determining the electric field due to each charge and adding them together as vectors.
Explanation:
The electric Field is a vector quantity, in other words it has a magnitude and a direction. On the other hand, the electric field follows the law of superposition. The electric field produced by two elements is equal to the sum of the electric fields produced by each element when the other element is not present. in other words, the total electric field is solved determining the electric field due to each charge and adding them together as vectors.
When an object's atoms move faster, its thermal energy increases and the object becomes warmer.
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
