Read each scenario below. Then select the answer that best completes each sentence.

Answer:

0.018 J

Explanation:

The work required to bring the charge from infinity to the point P is equal to the change in its electric potential energy. This can be expressed as

where

represents the charge's magnitude

and signifies the potential difference between point P and infinity.

After substituting into the formula, we arrive at

Answer:

The acceleration of the platform is - 1.8 m/s²

Explanation:

The net force on a body causes that body to accelerate in the direction of the resultant force applied.

Setting up the force equilibrium for the configuration:

ma = 800 - mg

100a = 800 - 100×9.8

100a = - 180

100a = - 180

a = - 1.8 m/s²

This indicates that the body is falling downward.

Answer: The calorimeter's heat capacity is

Explanation:

This scenario assumes the amount of heat lost by the hot object equals the amount of heat gained by the cold object.

where,

= specific heat capacity of water =

= specific heat capacity of calorimeter =?

= mass of water = 108.7 g

= mass of calorimeter = 108.7 g

= final temperature of the mixture =

= initial temperature of the water =

= initial temperature of calorimeter =

Now substituting all provided values into the formula, we obtain

Hence, the heat capacity of the calorimeter is

Answer:

1)  g = 4π² / m, 3) on the x-axis we have the pendulum lengths, while the y-axis shows the squared periods.

Explanation:

a) learners can model this system as a simple pendulum, where the angular velocity is given by

         w = √ g / l

Here, angular velocity, frequency, and period are interconnected:

         w = 2π f = 2π / T

Substituting yields:

         T = 2π√ l / g

Using this formula, students can calculate the gravitational acceleration by measuring the period for several pendulum lengths and plotting:

        T² = 4π²  l / g

We plot T² against l.

This represents a linear equation where T² is on the y-axis and l is on the x-axis:

        y = (4π² / g) l

The slope is given by:

         m = 4π² / g

Solving for g gives:

         g = 4π² / m

The slope is determined from the line's values rather than experimental data.

2) To perform the experiment, the string is secured to the sphere, then the pendulum length from the pivot to the sphere's center is measured using a tape measure. A slight angle (less than 10 degrees) is released, allowing the first swing to occur. Generally, the time for several oscillations, usually 10 or 20, is tracked to find the period:

    T = t / n

Next, a table is created comparing T² to the length, plotted with length on the x-axis to find the slope, from which the gravitational acceleration is derived.

3) The independent variable, which is the length of the pendulums, is plotted on the x-axis, while the dependent variable, the squared period, is on the y-axis.

4) Referring to the line equation:

            m = 4π² / g

             resulting in:

            g = 4π² / m

5) Once the spring is cut, the sphere continues to be influenced by gravitational acceleration. The harmonic motion ceases, and the sphere moves vertically.

A tennis player recovering from an ankle injury, restricted from pivoting, can keep her cardiovascular fitness by using the rowing machine, pedaling on a stationary bike with one leg, or swimming. These exercises do not necessitate directional changes and are safe for her injury.