Answer= 12.5 km
0.5 km x km
_______=______
1 min 25 min
Cross multiply
1x=12.5
divide both sides by 1
x=12.5
You traveled 12.5 km
Answer:
t=1.4hours
Explanation:
The half life is 1hour
At t=0 he has a mass of 4kg
So he want it to be 1kg, so that his weapon can work.
Applying the exponential function of decay
M=Cexp(-kt)
Where,
M is the mass at any time
C is a constant of integration
k is the rate of decay
Given that it has an half life of 1 hours.
Then k is 1
At t =0 the mass is 4kg
Therefore
4=Cexp(0)
C=4
M=4exp(-kt)
Since rate of decay is 1, then k=1
M=4exp(-t)
We need to find t at M=1kg
1=4exp(-t)
1=4exp(-t)
1/4=exp(-t)
0.25=exp(-t)
Take In of both sides
In(0.25)=-t
-1.3863=-t
Then, t=1.386hour
Then it will take about 1.4 hours to get to 1kg.
Answer:
20 J
Explanation:
Given:
Weight of the book is, 
Height or displacement of the book is, 
The work done on the book to raise it to a height of 2 m on a shelf is against gravity. The gravitational force acting on the book is equal to its weight. Now, in order to raise it, an equal amount of force must be applied in the opposite direction.
So, the force applied by me should be equal to weight of the body and in the upward direction. The displacement is also in the upward direction.
Now, work done by the applied force is equal to the product of force applied and displacement of book in the direction of the applied force.
Therefore, work done is given as:
Therefore, the work done to raise a book to a height 2 m from the floor is 20 J.
The reason as to why the substage condenser does not need to be included in computing the magnification and the only component needed is the ocular lens and the objective lenses is because the condenser is only responsible for gathering light and it does not contribute with the magnification of the object under the microscope.
Answer:
we learned that an object that is vibrating is acted upon by a restoring force. The restoring force causes the vibrating object to slow down as it moves away from the equilibrium position and to speed up as it approaches the equilibrium position. It is this restoring force that is responsible for the vibration. So what forces act upon a pendulum bob? And what is the restoring force for a pendulum? There are two dominant forces acting upon a pendulum bob at all times during the course of its motion. There is the force of gravity that acts downward upon the bob. It results from the Earth's mass attracting the mass of the bob. And there is a tension force acting upward and towards the pivot point of the pendulum. The tension force results from the string pulling upon the bob of the pendulum. In our discussion, we will ignore the influence of air resistance - a third force that always opposes the motion of the bob as it swings to and fro. The air resistance force is relatively weak compared to the two dominant forces.
The gravity force is highly predictable; it is always in the same direction (down) and always of the same magnitude - mass*9.8 N/kg. The tension force is considerably less predictable. Both its direction and its magnitude change as the bob swings to and fro. The direction of the tension force is always towards the pivot point. So as the bob swings to the left of its equilibrium position, the tension force is at an angle - directed upwards and to the right. And as the bob swings to the right of its equilibrium position, the tension is directed upwards and to the left. The diagram below depicts the direction of these two forces at five different positions over the course of the pendulum's path.
that's what I know so far
