In a problem where a child is danger form drowning from a river who has a current of 3.1km/hr to east and the child is 0.6km fro the shore and the upstream is 2,5km from the dock. So base on the question the boat with a speed of 24.8 km/hr is 1.9 km because the child is 0.6 km off the dock so 2.5 minus 0.6
Answer:
v = 0.42m/s
Explanation:
In order o calculate the linear speed of the point at the border of the wheel, you first take into account that the total acceleration of such a point is given by:
(1)
atotal: total acceleration = 1.2m/s^2
ar: radial acceleration of the wheel
at: tangential acceleration
The tangential acceleration is also given by:
(2)
r: radius of the wheel = (40cm/2 )= 20cm = 0.2m
α: angular acceleration = 4.0rad/s^2
You replace the expression (2) into the expression (1) and solve for the radial acceleration:

Next, you use the following formula for the radial acceleration and solve for the linear speed:

The linear speed of the point at the border of the wheel is 0.42m/s
Answer:
Explanation:
Given that
Beam current (i)=23.3µA
And the time to strike(t)=28s
Also, a fundamental charge e=1.602×10^-19C
Then, the charge quantity is given as,
q=it
Then, q=23.3×10^-6×28
q=6.524×10^-4C
Also, the number of electron N is given as
q=Ne
Therefore, N=q/e
So, N=6.524×10-4/1.602×10^-19
N=4.072×10^15
There are 4.072×10^15 electrons strike the tube screen every 28 s.
Answer:
When a bullet is fired from a gun, the gun exerts a force on the bullet in the forward direction. This is force is called as the action force. The bullet also exerts an equal and opposite force on the gun in the backward direction. Therefore a gun recoils when a bullet is fired from it.
Answer: C
Explanation:
when more volts are in a battery the more current you receive.