Answer:
Option"B" is correct.
Explanation:
when a body move with constant velocity then acceleration is zero.
Answer:
decreases
Explanation:
The angular frequency of the mass is given by
where, k is the spring constant and m be the mass of the body which is doing oscillations.
if the mass of the body increases, so the value of angular frequency decreases, as the angular frequency is inversely proportional to the square root of the mass of the body.
Answer:
The height of the platform is 22.686 m.
Explanation:
Given;
initial velocity of Janet, u = 2.63 m/s
time of her motion, t = 1.9 s
The height of the platform is given by;
h = ut + ¹/₂gt²
substitute the given values and solve for height "h"
h = (2.63 x 1.9) + ¹/₂(9.8)(1.9)²
h = 4.997 + 17.689
h = 22.686 m
Therefore, the height of the platform is 22.686 m.
I. Positive acceleration increases velocity. Negative acceleration decreases velocity. runner A sped up until the finish line and then slowed to a stop.
ii. Zero a acceleration implies a constant, unchanging velocity not a zero velocity. runner B achieved some velocity prior to 8s and is moving and must slow down to reach a stop.
iii. None. No aspects of this reasoning are correct. Everything she says is wrong. See iv for what/why.
iv. The sign on acceleration denotes the direction of *change in velocity* not change in direction. The sign on velocity can denote change in direction but only “forward” or “reverse” along a particular path. Cardinal direction is not indicated, generally, by the sign on velocity. It may correspond to North/South situationally but it is not an built-in feature of velocity and its sign. For example, if you are traveling with positive velocity and turn left to continue your journey you still have a positive velocity in the new direction. In fact, if you turn left again, traveling in the opposite direction as the one you started with your velocity would still be positive… in the new direction. The velocity relative to original direction could be said to be negative but that would be a confusing way to describe a journey. Maybe if you stopped the vehicle and moved in reverse, you could meaningfully say velocity was negative.
<span>If the force is fn, then it acting on the block, in the term of f2 and the other variables of the problems. then we assume the surface is rest on it's rigid, then the magnitude of the force is,
fn =f2 sin(?) +m g</span>
