Answer:
15s
Explanation:
Given parameters:
Distance traveled = 375m
Speed = 25m/s
Unknown:
Time taken = ?
Solution:
To solve this problem, we make time the subject of the speed equation.
Speed =
Time =
Now insert the parameters and solve;
Time =
= 15s
The vectors adition we can find the magnitude of the force applied by the other astronaut is 11.25 N in the y direction
Parameters given
- Force of an astronaut Fₓ = 42 N
To find
The force is a vector magnitude for which the addition of vectors must be used, a very efficient method to perform this sum is to add the components of each vector and devise constructing the resulting vector using trigonometry and the Pythagorean theorem.
Let's use trigonometry to find the other force
tan θ =
F_ y = Fₓ tan θ
let's calculate
F_y = 42 tan 15
F_y = 11.25 N
Using the summation of vectors we can find the magnitude of the force applied by the other astronaut is 11.25 N in the y direction
Learn more about vector addition here:
brainly.com/question/15074838
Answer:
ΔS total ≥ 0 (ΔS total = 0 if the process is carried out reversibly in the surroundings)
Explanation:
Assuming that the entropy change in the aluminium bar is due to heat exchange with the surroundings ( the lake) , then the entropy change of the aluminium bar is, according to the second law of thermodynamics, :
ΔS al ≥ ∫dQ/T
if the heat transfer is carried out reversibly
ΔS al =∫dQ/T
in the surroundings
ΔS surr ≥ -∫dQ/T = -ΔS al → ΔS surr ≥ -ΔS al = - (-1238 J/K) = 1238 J/K
the total entropy change will be
ΔS total = ΔS al + ΔS surr
ΔS total ≥ ΔS al + (-ΔS al) =
ΔS total ≥ 0
the total entropy change will be ΔS total = 0 if the process is carried out reversibly in the surroundings
Answer:
D. has no overall force acting on it.
Explanation:
Why?
Because in a straight line at the constant speed means the car moving in the same velocity, which is not acceleration neither deceleration, and it cannot be on a downhill slope. So the correct answer is
<h3>→ D. has no overall force acting on it.</h3>
Answer:

Explanation:
given,
frequency of tuba.f = 64 Hz
Speed of train approaching, v = 8.50 m/s
beat frequency = ?
using Doppler's effect formula

v_s is the velocity of the source
v is the speed of sound, v = 340 m/s
now,

f' = 65.64 Hz
now, beat frequency is equal to



hence, beat frequency is equal to 1.64 Hz