What is the measure of a change in an object’s velocity?

A gun can fire a bullet at 540 m/s. If the gun is aimed at an angle of 55o above the horizontal and fired, what will be the hori

lisabon 2012 [21]

Answer:

Explanation:

The initial vertical velocity is 540sin55° = 442.342103... 442 m/s

The initial horizontal velocity is 540cos55° = 309.731275... 310 m/s

In the real world, both initial velocities would be reduced by air resistance and vertical velocity will be altered by gravity.

5 0

3 years ago

A vertical spring with stiffness k originally is at rest with no mass attached. Then, a mass M is attached, and the spring rocks

Alina [70]

Answer:

The position of the spring in terms of g, m & k is $x = \frac{m g}{k}$

Explanation:

Stiffness of the spring = k

Mass = m

When a mass m is attached with the spring then spring stretched. in that case the force exerted on the spring is equal to weight of the mass attached.

⇒ Force exerted on the spring F = k x

⇒ m g = k x

⇒ $x = \frac{m g}{k}$

This is the position of the spring in terms of g, m & k.

8 0

3 years ago

Consider a parachutist that has reached terminal velocity. which of the following is true? A.) The acceleration of the parachuti

trasher [3.6K]

The correct answer is:
B.) At terminal velocity there is no net force

In fact, when the parachutist reaches the terminal velocity, his velocity does not change any more. It means that the acceleration acting on the parachutist is zero, and for Newton's second law, this means the net force acting on him is zero:
 $\sum F = ma = 0$
because the acceleration is zero: a=0.
This also means that the two relevant forces acting on the parachutist (gravity, downward, and air resistance, upward) are balanced to produce a net force equal to zero.

8 0

3 years ago

. What is the single most important equation in all of physics?

vivado [14]

Answer: F = ma,

Explanation:

the most famous equation in physics, establishing an equivalence between energy and mass. But is this the most important equation in physics? Knowledgeable scientists will tell you no. The most important equation in physics is F = ma, also known as Newton's second law of mechanics.

7 0

3 years ago

During a normal reaction to a stressful event, muscles are moved to their maximum capacity, and sensitivity is

Aleonysh [2.5K]

Answer:

The paper focuses on the biology of stress and resilience and their biomarkers in humans from the system science perspective. A stressor pushes the physiological system away from its baseline state toward a lower utility state. The physiological system may return toward the original state in one attractor basin but may be shifted to a state in another, lower utility attractor basin. While some physiological changes induced by stressors may benefit health, there is often a chronic wear and tear cost due to implementing changes to enable the return of the system to its baseline state and maintain itself in the high utility baseline attractor basin following repeated perturbations. This cost, also called allostatic load, is the utility reduction associated with both a change in state and with alterations in the attractor basin that affect system responses following future perturbations. This added cost can increase the time course of the return to baseline or the likelihood of moving into a different attractor basin following a perturbation. Opposite to this is the system's resilience which influences its ability to return to the high utility attractor basin following a perturbation by increasing the likelihood and/or speed of returning to the baseline state following a stressor. This review paper is a qualitative systematic review; it covers areas most relevant for moving the stress and resilience field forward from a more quantitative and neuroscientific perspective.

Explanation:

8 0

2 years ago