If you are sitting on a school bus, is the driver in motion (according to your

A ball has a mass of 1.5kg and is thrown straight up with a speed of 60m/s, what is the ball’s momentum:

madam [21]

Answer:

Assumption: the air resistance on this ball is negligible. Take $g = 10\; \rm m \cdot s^{-2}$ .

a. The momentum of the ball would be approximately $60\;\rm kg \cdot m \cdot s^{-1}$ two seconds after it is tossed into the air.

b. The momentum of the ball would be approximately $\rm \left(-45\; \rm kg \cdot m \cdot s^{-1}\right)$ three seconds after it reaches the highest point (assuming that it didn't hit the ground.) This momentum is smaller than zero because it points downwards.

Explanation:

The momentum $p$ of an object is equal its mass $m$ times its velocity $v$ . That is: $\vec{p} = m \cdot \vec{v}$ .

Assume that the air resistance on this ball is negligible. If that's the case, then the ball would accelerate downwards towards the ground at a constant $g \approx -10\; \rm m \cdot s^{-2}$ . In other words, its velocity would become approximately $10\; \rm m \cdot s^{-1}$ more negative every second.

The initial velocity of the ball is $60\; \rm m \cdot s^{-1}$ . After two seconds, its velocity would have become $60\;\rm m \cdot s^{-1} + 2\; \rm s \times \left(-10\;\rm m \cdot s^{-1}\right) = 40\; \rm m \cdot s^{-1}$ . The momentum of the ball at that time would be around $p = m \cdot v \approx 60\; \rm kg \cdot m \cdot s^{-1}$ .

When the ball is at the highest point of its trajectory, the velocity of the ball would be zero. However, the ball would continue to accelerate downwards towards the ground at a constant $g \approx -10\; \rm m \cdot s^{-2}$ . That's how the ball's velocity becomes negative.

After three more seconds, the velocity of the ball would be $0\; \rm m \cdot s^{-1} + 3\; \rm s \times \left(-10\; \rm m \cdot s^{-2}\right) = -30 \; \rm m \cdot s^{-1}$ . Accordingly, the ball's momentum at that moment would be $p = m \cdot v \approx \left(-45\; \rm kg \cdot m \cdot s^{-1}\right)$ .

3 0

3 years ago

An airtight box has a removable lid of area 1.00 10-2 m2 and negligible weight. the box is taken up a mountain where the air pre

gladu [14]

<span>9.50x10^2 newtons A pascal is defined as 1 newton per square meter. So let's multiply the pressure by the surface area of the box lid. F = 1.00x10^-2 m^2 * 9.50x10^4 N/m^2 = 9.50x10^2 N So it will take 9.50x10^2 newtons of force to remove the lid from the box.</span>

8 0

3 years ago

A chair exerts a force of 20 N on a floor and is not moving. What force does

AysviL [449]

The floor exerts 20 N of force on the chair

Explanation:

We can answer this question by using Newton's third law, which states that:

<em>"When an object A exerts a force (called action) on an object B, object B exerts an equal and opposite force (called reaction) on object A"</em>

In this problem, we can identify:

- Object A as the chair

- Object B as the floor

This means that the force of 20 N exerted by the chair on the floor is the action, and so the force exerted by the floor on the chair is the reaction. Newton's third law states that these two forces are equal and opposite: therefore, the force exerted by the floor on the chair is also 20 N, but in the opposite direction.

Learn more about Newton's third law:

brainly.com/question/11411375

#LearnwithBrainly

8 0

2 years ago

Tech A says that as engines gain miles, the spark plug gap increases, which raises the ignition system’s available voltage. Tech

Ugo [173]

Answer: Tech A is correct

Explanation:

Every vehicle has ignition system and without this system,it will not work. The battery of everything vehicle contain energy that start the vehicle and ignore it to start working. Electrical current move from the vehicle's battery and get to the induction coil, the induction coil increases the voltage in it so that the plug will be ignited. The spark plugs produce fire. The spark plug is connected to the ignition system. Once voltage is produced from the induction coil, electrical impulses move from induction coil to insulated plug wires. The spark plug need a very high voltage from the small voltage battery. Once the high voltage exceed the dielectric strength of the gases, spark jump the gap between the plug's fire end.

8 0

3 years ago

At what height h above the ground does the projectile have a speed of 0.5v?

dedylja [7]

Answer:height above ground at which projectile have velocity

0.5v is (0.0375v^2)

Explanation:

Using Vf = Vi - gt

Where Vf is final velocity

Vi is initial velocity

g is the acceleration due to gravity

t is the time taken

So, 0.5v = v - gt

t = 0.05v

Therefore height h = vt - 0.5gt^2

Subtitute t

h = 0.05v^2 - 0.0125v^2

h = 0.0375v^2

3 0

2 years ago