Newton would agree that all objects on Earth exert a

At a particular instant, a moving body has a kinetic energy of 295 J and a momentum of magnitude 25.1 kg · m/s.(a)What is the sp

motikmotik

Answer:

a) 23.51 m/s

b) 1.07 kg

Explanation:

Parameters given:

Kinetic energy, K = 295 J

Momentum, p = 25.1 kgm/s

a) The kinetic energy of a body is given as:

$K = \frac{1}{2} mv^2$

where m = mass of the body and v = speed of the body

We know that momentum is given as:

p = mv

Therefore:

K = 1/2 * pv

=> v = 2K / p

v = (2 * 295) / 25.1 = 23.51 m/s

The velocity of the body at that instant is 23.51 m/s.

b) Momentum is given as:

p = mv

=> m = p / v

m = 25.1 / 23.51 = 1.07 kg

The mass of the body at that instant is 1.07 kg

5 0

3 years ago

A small sphere is hung by a string from the ceiling of a van. When the van is stationary, the sphere hangs vertically. However,

Paraphin [41]

Answer: 42.49 $m/s^{2}$

Explanation:

To solve this, we need to keep in mind the following:

While the sphere hangs it is under the effect of gravity. It is creating a Angle of 90° taking the roof as a reference.

Gravity can be noted as a Acceleration Vector. The magnitud for Earth's Gravity is a constant: 9.81 $m/s^{2}$

The acceleration of the Van will affect the sphere also, but this accelaration will be on the X-axis and perpendicular to the gravity. Because this two vectors are taking action under the sphere they will create a angle. This angle can be measured as a relation of the two magnitudes.

Tangent (∅) = Opossite Side / Adyacent Side

By trigonometry, we know the previous formula. This formula allows us to find the Tangent of a angle as a relation between the two perpendiculars magnitudes. In this case the Opossite Side will be the Gravity Accelaration, while the Adyancent Side is the Van's Acceleration.

(1) Tangent (∅) = Gravity's Acceleration (G) / Van's Acceleration (Va)

Searching for the Va in (1)

Va = G/Tan(∅)

Where ∅ in this case is equal to 13.0°

Va = 9.81 $m/s^{2}$ / Tan(13.0°)

Va = 42.49 $m/s^{2}$

The vans acceleration need to be 42.49 $m/s^{2}$ to create an angle of 13° with the Van's Roof

3 0

3 years ago

What happens to a circuit's resistance (R), voltage (V), and current (1) when

hammer [34]

Answer:

D.

R increases

V is constant

I decreases

Explanation:

The resistance of a wire is given by the following formula:

$R = \frac{(Resistivity)(L)}{A}$

It is clear from this formula that resistance is directly proportional to the length of wire. So, when length of wire is increased, the resistance of circuit increases.

The voltage in the circuit will be constant as the voltage source remains same and it is not changed.

Now, we can use Ohm Law:

V = IR

at constant V:

I ∝ 1/R

it means that current is inversely proportional to resistance. Hence, the increase of resistance causes the current in circuit to decrease.

Therefore, the correct option will be:

D.

R increases

V is constant

I decreases

6 0

2 years ago

Which one of the following acts is an example of body language?

Viktor [21]

Rolling of the eyes. The person is either vexed or frustrated.

6 0

3 years ago

Read 2 more answers

Kai takes a hamburger off of the grill and puts a piece of cheese on it. Explain how and why the cheese melts when Kai puts it o

Yanka [14]

Because the hamburger is still hot from the grill, the cheese melts because of that heat.

3 0

3 years ago

Read 2 more answers