Answer:
The speed change during the 45-minute trip is 20[mph]
Explanation:
When we see the speed at the 45 minutes this is 20 [mph] and at the 0 minutes the speed is 0 [mph].
Therefore the change is (20 - 0) = 20 [mph]
In the attached image we can see the different figures. In fig 1 we can see the bicycle's speed after 10 minutes when the speed becames constant.
In the fig. 2 we can find the graph when the biker stopped at 30 minutes and took a 15-minute break.
Figures 3 and 4, show the differences when a horizontal line is traced on a position vs time graph, and when the horizontal line is traced in a speed vs time graph.
For fig 3 we can conclude that the body is not moving therefore there is no velocity or acceleration. And for the fig 4, we can realize that the area under the horizontal line represents a displacement during the respective interval of time.
Answer:
B = 1.1413 10⁻² T
Explanation:
We use energy concepts to calculate the proton velocity
starting point. When entering the electric field
Em₀ = U = q V
final point. Right out of the electric field
em_f = K = ½ m v²
energy is conserved
Em₀ = Em_f
q V = ½ m v²
v =
we calculate
v =
v =
v = 25.15 10⁴ m / s
now enters the region with magnetic field, so it is subjected to a magnetic force
F = m a
the force is
F = q v x B
as the velocity is perpendicular to the magnetic field
F = q v B
acceleration is centripetal
a = v² / r
we substitute
qvB =1/2 m v² / r
B = v
we calculate
B =
B = 1.1413 10⁻² T
Answer:
(D ) and
Explanation:
Given that, the rms value of current is 10 ampere and its frequency is 50 Hz.
Now maximum value of current can be calculated as,
The time period is defined as,
Now the time taken by alternating current going from zero to maximum value is,
Therefore, the time taken by alternating current to reach maximum value is and the peak value of current is .
Energy cannot be created nor be destroyed
Force is equal to mass x acceleration. The heavyweight is packing both greater acceleration and mass than the tissue paper.
When his fist comes in contact with the paper, the tissue reacts by exerting its own opposite force, providing a tiny bit of resistance until the fist breaks it apart and passes through.
The fist, although by a a very tiny amount, is decelerated (slowed down) by the paper before it breaks through.