Answer:
RIGHT
Explanation:
given,
mass of box = 250 kg
speed of the truck = 25 m/s
static friction µs = 0.7
g = 10 m/s²
to find direction of friction on the box
truck is moving in left direction and suddenly in front of truck a car stops then the driver hit the brake hard so at that moment the box on the trailer will have the tendency to move left so to oppose its movement friction force will be on RIGHT
Answer:
Approximately 
(approximately 
) assuming that the magnetic field and the wire are both horizontal.
Explanation:
Let 
denote the angle between the wire and the magnetic field.
Let 
denote the magnitude of the magnetic field.
Let 
denote the length of the wire.
Let 
denote the current in this wire.
The magnetic force on the wire would be:
.
Because of the 
term, the magnetic force on the wire is maximized when the wire is perpendicular to the magnetic field (such that the angle between them is 
.)
In this question:
(or, equivalently, 
radians, if the calculator is in radian mode.)
.
.
.
Rearrange the equation 
to find an expression for , the current in this wire.
.
First of all, the question is worded somewhat ambiguously because mass does not necessarily imply that there is a force (i.e. an object could be stationary in a system with no gravity and not have a force, or something of the like). Moreover, simply because an object is twice the mass does not mean the force will change.
However, we know from Newton's second law that F = ma. Therefore, force will increase or decrease proportionally with mass. This means if an object maintains a contestant acceleration and its mass doubles, the force that it provides will also double.
To solve this problem it is necessary to apply the concepts related to thermal linear expansion. Mathematically this concept can be expressed under the Equation:
Where,
Initial Length
Thermal Expanssion constant
Change in Lenght
Our values are given as
Replacing at our equation we have,
Therefore the expantion of the bar is 0.317mm
Answer:
O 47 kg. m/s if they were initially headed opposite direction
O 145 kg. m/s if they were initially headed the same direction
The other two are possibilities as well if velocities are initially at an angle
Explanation:
