Heya!!
For calculate aceleration, lets applicate second law of Newton:

<u>Δ Being Δ</u>
F = Force = 78,3 N
m = Mass = 24,5 kg
a = Aceleration = ?
⇒ Let's replace according the formula and clear "a":

⇒ Resolving

Result:
The aceleration is <u>3,19 meters per second squared (m/s²)</u>
Good Luck!!
Answer:
Option A
Explanation:
The Equation represents the displacement of the object which is represented by x

so,
means when time is zero so we replace t with zero in the equation,

now for v which is velocity we need to differentiate the function as the formula for velocity is rate of change of displacement over time so we derivate the equation once and get,

now for
we insert t = 0 and get

now for a which is acceleration the formula of acceleration is rate of change of velocity over time, so we differentiate the the equation of v(velocity) once or the equation of x(displacement) twice so now we get,

so Option A is your answer.
Remember derivative of a constant is always zero because a constant value has no rate of change has its a constant hence the derivative is 0
Answer: A and B
Explanation:
Electromagnetic radiations are examples of electromagnetic waves with increasing frequency and decreasing wavelength in the following order radiowaves - infrared waves - visible lights - ultraviolet rays- x-rays - gamma rays.
They did not require material medium for their propagation.
The statement above shows that EM radiations possesses different wavelengths and frequency.
Answer:
The existance of dark energy was suggested to help explain measurements, using Type Ia supernovae as distance indicators, that the expansion of the universe is speeding up and its acceleration requires a source of energy. Scientists suggested that It may be a new form of energy for which there is not yet a theoretical explanation. quantum mechanics predict that it may be the vacuum energy associated with "empty" space itself.
Answer:
Mass of the disk will be 2.976 kg
Explanation:
We have given force F = 45 N
Radius of the disk r = 0.12 m
Angular acceleration 
We know that torque 
And 
So
, here I is moment of inertia
So 

We know that moment of inertia 
So 
m = 2.976 kg