Answer:
Gravity acts to pull the object down.
The object’s inertia carries it forward.
The path of the object is curved.
Explanation:
The motion of a projectile consists of two separate motions:
- A uniform motion along the horizontal direction, where the velocity is constant; since there are no forces along this direction, the velocity does not change, and so the object continues its motion for inertia --> so, the statement "The object’s inertia carries it forward" is true.
- A uniformly accelerated motion along the vertical direction, with a constant downward acceleration (g=9.8 m/s^2, acceleration due to gravity). So, the vertical velocity changes, due to the presence of the gravity that acts to pull the object down.
- As a result of the combination of these two motions, the object follows a curved path (in particular, it is a parabolic path).
In the mid of the 19th century the miasma theory was replaced by the germ theory of diseases (Maia 2013) The Greek physician Hippocrates (c.460- 377 B.C.E) believed that bad air could be the cause of any pestilences, the fatal epidemic.
Hope that helps!
Answer:
B
Explanation:
Water level remains unchanged
The first thing to realize is that the buoyancy force is the same as, or equal to the weight of the wood, this same force is also the same as or equal to the weight of the water displaced by the wood. In the two cases, the weight of the wood will be unaffected nonetheless, and thus the water level will remain the same.
Therefore, the answer is B, the water level remains unchanged.
Complete question:
What is the peak emf generated by a 0.250 m radius, 500-turn coil is rotated one-fourth of a revolution in 4.17 ms, originally having its plane perpendicular to a uniform magnetic field 0.425 T. (This is 60 rev/s.)
Answer:
The peak emf generated by the coil is 15.721 kV
Explanation:
Given;
Radius of coil, r = 0.250 m
Number of turns, N = 500-turn
time of revolution, t = 4.17 ms = 4.17 x 10⁻³ s
magnetic field strength, B = 0.425 T
Induced peak emf = NABω
where;
A is the area of the coil
A = πr²
ω is angular velocity
ω = π/2t = (π) /(2 x 4.17 x 10⁻³) = 376.738 rad/s = 60 rev/s
Induced peak emf = NABω
= 500 x (π x 0.25²) x 0.425 x 376.738
= 15721.16 V
= 15.721 kV
Therefore, the peak emf generated by the coil is 15.721 kV
In Physics, 'work' has a very clear definition:
It's (strength of a force) times (distance through which the force acts).
'Work' has the units of Energy.
If you push against a shopping cart with 30 newtons of force, and
you keep pushing while the cart moves 4 meters, then you have
done (30 x 4) = 120 newton-meters of work = 120 "Joules".
