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3 years ago

1. What is meant by half-life?

1 answer:

8 0

1. The time for a radioactive sample to reduce to half of its original mass.
4. 10% of 232 is 23.2 times 6 equals 139.2
68.9 x6 equals 413.4
5. 0.37kg
6. 2000 years
7. 6.84 seconds

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At an instant when a soccer ball is in contact with the foot of the player kicking it, the horizontal or x component of the ball

Ymorist [56]

Answer:440.03 N

Explanation:

Given

horizontal component of acceleration $(a_x)=800 m/s^2$

vertical component of acceleration $(a_y)=880 m/s^2$

mass of ball =0.37 kg

Force in horizontal direction $=m\times a_x=0.37\times 800=296 N$

Force in vertical direction $=m\times a_y=0.37\times 880=325.6 N$

Therefore net force is

$F=F_x+F_y$

$|F|=\sqrt{296^2+325.6^2}$

|F|=440.03 N

5 0

3 years ago

A ball accelerates from rest down a ramp at 2.4 m/s^2. Write an equation that could be used to determine the balls finals positi

Alik [6]

Answer:

x=2.4t+4.9t^2

Explanation:

This equation is one of the kinematic equations to solve for distance. The original equation is as follows:

X=Xo+Vt+1/2at^2

We know that the ball starts at rest meaning that its initial velocity and position is zero.

X=0+Vt+1/2at^2

Since it is going down the ramp, you can use the acceleration of gravity constant. (9.81 m/s^2) and simplify that with the 1/2.

X=Vt+4.9t^2

Note: Since the positive direction in this problem is down, you are adding the 4.9t^2, but if a question says that the downward direction is negative, you would subtract those values.

Now, substitute in your velocity value.

X=2.4t+4.9t^2

8 0

2 years ago

On earth, two parts of a space probe weigh 14500 N and 4800 N. These parts are separated by a center-to-center distance of 18 m

Nastasia [14]

Answer:

$F = 1.489*10^{-7} N$

Explanation: Weight of space probes on earth is given by: $W= m*g$

W= weight of the object( in N)

m= mass of the object (in kg)

g=acceleration due to gravity(9.81 $\frac{m}{s^{2} }$ )

Therefore,

$m_{1} = \frac{14500}{9.81}$

$m_{1} = 1478.08 kg$

Similarly,

$m_{2} = \frac{4800}{9.81}$

$m_{2} = 489.29 kg$

Now, considering these two parts as uniform spherical objects

Also, according to Superposition principle, gravitational net force experienced by an object is sum of all individual forces on the object.

Force between these two objects is given by:

$F = \frac{Gm_{1} m_{2}}{R^{2} }$

G= gravitational constant ( $6.67 * 10^{-11} m^{3} kg^{-1} s^{-2}$ )

$m_{1} , m_{2}$ = masses of the object

R= distance between their centres (in m)(18 m)

Substituiting all these values into the above formula

$F = 1.489*10^{-7} N$

This is the magnitude of force experienced by each part in the direction towards the other part, i.e the gravitational force is attractive in nature.

7 0

3 years ago

What does fossil fuels do?

katrin [286]

Fossil fuel are collected and turned into oils like car gas and many other products have fossil fuels in them and we don't even realize it idk oil was made out of fossils till i studied fossils in class Hope this helps:)

8 0

3 years ago

Read 2 more answers

Two people push on the same door from opposite sides as shown. A man pushes on a door from the left. A woman pushes on the door

AURORKA [14]

Answer:

The door will move when the forces exerted by each individual becomes unbalanced.

Explanation:

The Door will only move when the forces exerted by each of the individual is unbalanced i.e. when the Torque is unbalanced

This is because there will only be a reaction or movement of an object when the applied force > resistant force acting on the object.

example : An object at rest will only move when the applied force is greater than the frictional forces acting on the object at rest.

8 0

2 years ago