Answer:
0J
Option: B
Explanation:
Work is done when something is moved by the force in the direction of the force. That is the force (e.g., the weight) and the direction the object moves must be aligned for work to be done. In this given condition, the direction is horizontal and the force is downward as its gravity force. That 90° between the two vectors.
The work function is W = m × g ×h × cosθ
Hence,
Work done = 7 × 9.8 × 1.5 × cos(90)
Work done = 0 (cos
= 0)
Work done = 0
Therefore work done is 0 J.
The study of the inorganic world.
40 km/h because the average of 50 and 30 is 40
The strength of the gravitational field is given by:
where
G is the gravitational constant
M is the Earth's mass
r is the distance measured from the centre of the planet.
In our problem, we are located at 300 km above the surface. Since the Earth radius is R=6370 km, the distance from the Earth's center is:
And now we can use the previous equation to calculate the field strength at that altitude:
And we can see this value is a bit less than the gravitational strength at the surface, which is
.
Answer:
C. Quadruple the intensity
Explanation:
The intensity of the sound is proportional to square of amplitude of the sound.
I ∝ A²
When the given sound is twice loud as the initial value, then the new amplitude is twice the former.
A₂ = 2A₁
Thus, to make a given sound seem twice as loud, the musician should Quadruple the intensity
