Define the strip attached to the magnet?

Directions: Consider a 2-kg bowling ball sits on top of a building that is 40 meters tall. It falls to the ground. Think about t

Ronch [10]

1. The bowling ball have more potential energy as it sit on top of the building

2.The bowling ball have same potential energy and kinetic energy as it is half way through its fall

3. The bowling ball have more kinetic energy just before it hits the ground

4. The potential energy of the bowling ball as it sits on top of the building is 784J

5. The potential energy of the ball as it is half way through the fall, 20 meters high is 392J

6. The kinetic energy of the ball as it is half way through the fall is 392J

7. The kinetic energy of the ball just before it hits the ground is 784J

Explanation:

Calculating potential energy and kinetic energy for all the instances,

1. ball on top of a 40 meters tall building

Potential energy at the top of building with a height of 40m = mgh

P.E = mgh =2*9.8*40= 784J

At the top pf the building since v=0 kinetic energy is zero

2. half way through a fall off a building that is 40 meters tall and travelling 19.8 meters per second

Potential energy when it is half way through fall = mgH

where H represents new height that is equal to 20m

hence P.E=mgH=2*9.8*20= 392J

Kinetic energy of the ball is $\frac{1}{2} mv^{2} = \frac{1}{2} *2*19.8^{2}$ =392.04J

3. Just about to hit the ground from a fall off a building that is 40 meters tall and travelling 28 meters per second.

The potential energy of ball just before it hits the ground = mgh= 2*9.8*0=0J

kinetic energy = $\frac{1}{2} mv^{2}$ = 784J

3 0

3 years ago

A rock is dropped from rest. How fast is it going after it has been falling for 9.2 s?

natka813 [3]

90.2 m/s. A rock dropped from rest after it has falling for 9.2 seconds will have a velocity of 90.2m/s.

The bodies left in free fall increase their speed (downwards) by 9.8 m/s² every second. The acceleration of gravity is the same for all objects and is independent of the masses of these. In the free fall the air resistance is not taken into account.

v = g*t

v = (9.8m/s²)(9.2s) = 90.2 m/s

6 0

4 years ago

Estimate the kinetic energy of the Mars with respect to the Sun as the sum of the terms, that due to its daily rotation about it

kotykmax [81]

Answer:

K = 2.07 10³⁹ J

Explanation:

This problem must be solved using rotational kinematics.

Kinetic energy has the form

K = ½ m v²

Linear velocity is related to angular velocity.

v = w r

replace

K = ½ m R² w²

With this equation we can find the total kinetic energy of Mars, formed by the rotation energy plus the translational energy

K = Kr + Kt

Where Kr is the energy by the rotation on its axis and Kt is the energy by the rotation around the sun.

Let's reduce to SI units

Rotation T₁ = 24.7 h (3600 s / 1 h) = 88920 s

R₁ = 3.4 10⁶ m

translation T₂ = 686 day (24 h / 1 day) (3600 s / 1 h) = 5.927 10⁷ s

R₂ = 2.3 10⁸ km (1000 m / 1 km) = 2.3 10¹¹ m

The angular velocity is the angle rotated (radians) between the time taken, in this case as the order gives us the angle is 2pi rad (360º). Remember that the equations work only in radians

Rotation

wr = 2π / T₁

wr = 2 π / 88920

wr = 7.066 10⁻⁵ rad / s

Translation

wt = 2 π / T₂

wt = 2 π / 5,927 10⁷

wt = 1.06 10⁻⁷-7 rad/s

Let's explicitly write the equation of kinetic energy and calculate

K = ½ m R₁² wr² + ½ m R₂² wt²2

K = ½ m (R₁² wr² + R₂² wt²)

K = ½ 6.4 10²³ [(3.4 10⁶)² 7.066² + (2.3 10¹¹)² (1.06 10⁻⁷)²]

K = 3.2 10²³ [61.49 10¹² + 6.414 10¹⁵]

K = 3.2 10²³ [61.49 10¹² + 6414 10¹²]

K = 3.2 10²³ (6475 10¹²)

K = 2.07 10³⁹ J

5 0

3 years ago

Add to the significant place: 20.1 + 2.00100 +48.28 + 0.015

chubhunter [2.5K]

Answer:

Explanation:

20.1 + 2.00100 +48.28 + 0.015 = 70.396 ≈ 70.4

3 s.f. 6 s.f. 4 s.f. 3 s.f 3 s.f

6 0

3 years ago

A farmhand pushes a 23 kg bale of hay 3.9 m across the floor of a barn. If she exerts a horizontal force of 91 N on the hay, how

uranmaximum [27]

Answer:

W = 354.9 J

Explanation:

Given that,

The mass of a bale of hay, m = 23 kg

The displacement, d = 3.9 m

The horizontal force exerted on the hay, F = 91 N

We need to find the work done. We know that,

We know that,

Work done, W = Fd

So,

W = 91 N × 3.9 m

W = 354.9 J

So, the required work done is 354.9 J.

4 0

3 years ago

Define the strip attached to the magnet?​

Define the strip attached to the magnet?