All categories

3 years ago

As a 2.0-kg object moves from (4.4 i + 5j) m to ( 11.6 i - 2j) m, the constant resultant force

Physics

1 answer:

fgiga [73]3 years ago

5 0

Answer: $107.8\ J$

Explanation:

Given

Initial position of object is (4.4 i+5 j)

Final position of object is (11.6 i -2 j)

Force acting (4i-9j)

Work done is given by

$\Rightarrow W=F\cdot dx\\\Rightarrow W=(4i-9j)\cdot (11.6i-4.4i-2j-5j)\\\Rightarrow W=(4i-9j)\cdot (7.2i-7j)\\\Rightarrow W=28.8+63\\\Rightarrow W=91.8\ J$

Initial kinetic energy

$K_i=\dfrac{1}{2}\times 2\times 4^2\\\\K_i=16\ J$

Change in kinetic energy is equal to work done by object

$\Rightarrow K_f=K_i+W\\\Rightarrow K_f=16+91.8\\\Rightarrow K_f=107.8\ J$

You might be interested in

Bob is pushing a box across the floor at a constant speed of 1.7 m/s, applying a horizontal force whose magnitude is 70 N. Alice

OlgaM077 [116]

Answer:

a) 70 N, b) b. Each initially applied a force bigger than static friction to get the box moving and accelerating, then when the desired final speed was achieved they reduced the force to make the net force zero.

Explanation:

a) A constant speed means that magnitude of friction force is equal to the magnitude of the external force. The friction force is directly proportional to the normal force, which is equal to the weight of the box. Therefore, the magnitude of the force is 70 N.

b) Alice used initially a greater force to accelerate the box up to needed speed and later reduced the external force to keep speed constant. The right choice is option b.

3 0

3 years ago

Jane placed two bar magnets on her desk next to each other with like poles facing. She then sprinkled some iron filings around t

viktelen [127]

Answer:

Explanation:

3 0

4 years ago

Read 2 more answers

Select the statement that best describes gravity.

pav-90 [236]

Explanation:

Gravity is the force of attraction between two objects. It depends upon the mass of the objects and the distance between the objects. Mathematically, the force of gravity is given by :

$F=G\dfrac{m_1m_2}{d^2}$

Where

G is the universal gravitational constant

$m_1\ and\ m_2$ are masses

d is the distance between two masses

So, statement (2) describes gravity "Gravity is the force of attraction between two objects; it is dependent upon the mass of the objects and the distance between the objects".

6 0

3 years ago

If a person traveled 475 miles at a rate of 74 miles per hour. how long did they travel for?

Gennadij [26K]

They traveled for six hours and forty two minutes

3 0

3 years ago

How is the combined gas law used to calculate changes in pressure, temperatures, and/or volume for a fixed amount of gas?

nalin [4]

Answer:

Let's start by considering the ideal gas law:

$pV=nRT$

where

p is the gas pressure

V is its volume

n is the number of moles

R is the gas constant

T is the absolute temperature

This equation can also be rewritten as

$\frac{pV}{T}=nR$

Now, if we consider a fixed amount of gas, this means that the number of moles (n) is constant. So we can rewrite the equation as

$\frac{pV}{T}=const.$

And therefore, if we consider a gas undergoing a certain transformation from 1 to 2, we can write

$\frac{p_1V_1}{T_1}=\frac{p_2V_2}{T_2}$

where 1 indicates the conditions of the gas at the beginning and 2 the conditions of the gas after the process. So, the change in pressure/temperature/volume of the gas can be found by using this equation.

5 0

3 years ago