25 kg
Explanation:
we can calculate the mass of the crate by using the Newton's second law:

where
F is the force acting on the crate
m is the mass
a is the acceleration
In this problem,
and
, so we can re-arrange the equation above to calculate the mass of the crate:

The correct is D.
Explanation: The specific heat is defined as heat required to raise the temperature of a unit mass by one degree. Greater the specific heat, more is the heat required to raise the temperature for equal mass. So, the temperature of the material with lowest specific heat will increase the most for the same amount of heat energy.
Answer:

Explanation:
Given:
- quantity of point charge,

- radial distance from the linear charge,

- linear charge density,

<u>We know that the electric field by the linear charge is given as:</u>



<u>Now the force on the given charge can be given as:</u>



D. distance = 23 m, displacement = + 1 m
Explanation:
Let's remind the difference between distance and displacement:
- distance is a scalar, and is the total length covered by an object, counting all the movements in any direction
- displacement is a vector connecting the starting point and the final point of a motion, so its magnitude is given by the length of this vector, and its direction is given by the direction of this vector.
In this case, the distance covered by Karen is given by the sum of all its movements:

The displacement instead is given by the difference between the final point (1.0 m in front of the starting line) and the starting point (the starting line, 0 m):

To stop instantly, you would need infinite deceleration. This in turn, requires infinite force, as demonstrable with this equation:F=ma<span>So when you hit a wall, you do not instantly stop (e.g. the trunk of the car will still move because the car is getting crushed). In a case of a change in momentum, </span><span><span>m<span>v⃗ </span></span><span>m<span>v→</span></span></span>, we can use the following equation to calculate force:F=p/h<span>However, because the force is nowhere close to infinity, time will never tend to zero either, which means that you cannot come to an instantaneous stop.</span>