To solve the exercise it is necessary to apply the concepts related to Newton's Second Law, as well as the definition of Weight and Friction Force.
According to the problem there is a movement in the body and it is necessary to make a sum of forces on it, so that

There are two forces acting on the body, the Force that is pushing and the opposing force that is that of friction, that is

To find the required force then,

By definition we know that the friction force is equal to the multiplication between the friction coefficient and the weight, that is to say





Therefore the horizontal force applied on the block is B) 230N
Answer:
centripetal force is calculated by mass(kg) × tangetial velocity(m/s) ÷ radius (m)
Explanation:
so 30000g= 30kg
50km/h = 13.88m/s
600cm= 6m
30×13.88÷6= 69.4N
N= Newton's
hope this helps.
btw I'm 16 and love physics so I tried my best in this hope it went well!!
Answer:
9.89 m/s.
Explanation:
Given that,
The radius of the circular arc, r = 25 m
The acceleration of the vehicle is 0.40 times the free-fall acceleration i.e.,a = 0.4(9.8) = 3.92 m/s²
Let v is the maximum speed at which you should drive through this turn. It can be solved as follows :

So, the maximum speed of the car should be 9.89 m/s.
Many of today’s mathematicians use computers to test cases that are either too time-consuming or involve too many variables to test manually, allowing the exploration of theoretical issues that were impossible to test a generation ago.
Answer: Option A
<u>Explanation:</u>
One of the most useful inventions in scientific world are the computers. We can use different programming language and create programs in them. These programs help other to solve difficult problems. Most of the theoretical problems in science can be solved by using these programming features in computer within a specific time limit.
Otherwise, earlier mathematician used to take months to solve a complex mathematical problem manually, but now with the inclusion of computers, the mathematician can solve the problems containing more number of variables or other theoretical issues.
Answer: When Reggie's car turned eastward, his books continued moving northward, causing them to slide off the top of his car. :)