Ask question

Ask question

All categories

2 years ago

8

An object of mass 0.9 kg is attached to a massless string of length 3 m, and swung with 3 a tangential velocity of 3 m/s. What i

s the force exerted by the string on the object?
a. 32 N
b. 27 N
C. 5 N
d. 2.7 N

1 answer:

Ganezh [65]2 years ago

5 0

Answer:

d

Explanation:

you have to divide by the square root and then use the factorial to multiply

You might be interested in

A space probe is fired as a projectile from the Earth's surface with an initial speed of 2.05 104 m/s. What will its speed be wh

Elanso [62]

Answer:

The value is $v = 2.3359 *10^{4} \ m/s$

Explanation:

From the question we are told that

The initial speed is $u = 2.05 *10^{4} \ m/s$

Generally the total energy possessed by the space probe when on earth is mathematically represented as

$T__{E}} = KE__{i}} + KE__{e}}$

Here $KE_i$ is the kinetic energy of the space probe due to its initial speed which is mathematically represented as

$KE_i = \frac{1}{2} * m * u^2$

=> $KE_i = \frac{1}{2} * m * (2.05 *10^{4})^2$

=> $KE_i = 2.101 *10^{8} \ \ m \ \ J$

And $KE_e$ is the kinetic energy that the space probe requires to escape the Earth's gravitational pull , this is mathematically represented as

$KE_e = \frac{1}{2} * m * v_e^2$

Here $v_e$ is the escape velocity from earth which has a value $v_e = 11.2 *10^{3} \ m/s$

=> $KE_e = \frac{1}{2} * m * (11.3 *10^{3})^2$

=> $KE_e = 6.272 *10^{7} \ \ m \ \ J$

Generally given that at a position that is very far from the earth that the is Zero, the kinetic energy at that position is mathematically represented as

$KE_p = \frac{1}{2} * m * v^2$

Generally from the law energy conservation we have that

$T__{E}} = KE_p$

So

$2.101 *10^{8} m + 6.272 *10^{7} m = \frac{1}{2} * m * v^2$

=> $5.4564 *10^{8} = v^2$

=> $v = \sqrt{5.4564 *10^{8}}$

=> $v = 2.3359 *10^{4} \ m/s$

4 0

2 years ago

Stars set about how many minutes earlier each day?<br><br> A. 8<br> B. 6<br> C. 4<br> D. 2

Furkat [3]

It is c which is four minutes per day

5 0

3 years ago

Please help this is really important thanks

Juliette [100K]

1. Giga is the largest
2. Stem-and-leaf

6 0

2 years ago

What is happening to the water molecules as it changes from ice to liquid water? *

g100num [7]

Answer:

They are gaining energy, can move and slide past each other.

Explanation:

Because as ice melts, the molocules gain energy/heat which warm them up and are able to slide/move apart from each other.

7 0

3 years ago

Two metal balls are the same size, but one weighs twice as much as the other. The balls are dropped from the top of a two story

seropon [69]

The time taken by the metal balls of the same size but different weight, to reach the ground will be the same.

Reason behind:

Two metal balls are the same size, but one weighs twice as much as the other. The balls are dropped from the top of a two-story building at the same instant of time. It is required to find the time taken by the balls to reach the ground.

In free fall, all objects experience the same acceleration owing to gravity when they are close to the earth.

$g=9.8 \text{ m/s}^2$ is the measure of gravitational acceleration.

Because of this, the two metal balls are the same size but have different masses. The air resistance for both balls will be the same due to their similar sizes. Let, g' be the acceleration in the presence of air resistance. The balls are both discharged at once.

From a height of h, both balls descend due to gravity G'.

Therefore, the time taken by both balls is:

$\begin{aligned}&s=u t+\frac{1}{2} g t^{2} \\&u=0, s=h \\&t=\sqrt{\frac{2 h}{g}}\end{aligned}$

Therefore, the time is independent of mass. Thus the time taken by both the balls, will be about the same.

Learn more about time taken by metal ball to reach the ground here,

brainly.com/question/22719691

#SPJ4

4 0

2 years ago