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2 years ago

The modern periodic table has______ groups. (Write your answer as a number.)

Physics

2 answers:

ss7ja [257]2 years ago

5 0

I think it has 18 groups

kobusy [5.1K]2 years ago

4 0

It contains 18 groups

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explain how many minimum number of geostationary satellites are required for global coverage of T.V transmission

kobusy [5.1K]

Answer:I honestly don't know

Explanation:

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3 years ago

Match these items.

horrorfan [7]

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2 years ago

Is cutting a string physcal or chemical change

oksano4ka [1.4K]

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3 years ago

Before colliding, the momentum of block A is -100 kg*m/, and block B is -150 kg*m/s. After, block A has a momentum -200 kg*m/s.

rjkz [21]

Answer:

Momentum of block B after collision = $-50\ kg\ ms^{-1}$

Explanation:

Given

Before collision:

Momentum of block A = $p_{A1}$ = $-100\ kg\ ms^{-1}$

Momentum of block B = $p_{B1}$ = $-150\ kg\ ms^{-1}$

After collision:

Momentum of block A = $p_{A2}$ = $-200\ kg\ ms^{-1}$

Applying law of conservation of momentum to find momentum of block B after collision $p_{B2}$ .

$p_{A1}+p_{B1}=p_{A2}+p_{B2}$

Plugging in the given values and simplifying.

$-100-150=-200+p_{B2}$

$-250=-200+p_{B2}$

Adding 200 to both sides.

$200-250=-200+p_{B2}+200$

$-50=p_{B2}$

∴ $p_{B2}=-50\ kg\ ms^{-1}$

Momentum of block B after collision = $-50\ kg\ ms^{-1}$

6 0

2 years ago

A cannon fired horizontally at 20 m/s from the top of a cliff lands 80m away. how tall is the cliff

Scorpion4ik [409]

Answer:

The height of the cliff is, h = 78.4 m

Explanation:

Given,

The horizontal velocity of the projectile, Vx = 20 m/s

The range of the projectile, s = 80 m

The projectile projected from a height is given by the formula

Therefore,

h = S²g/2Vx²

Substituting the values

h = 80² x 9.8/ (2 x 20²)

= 78.4 m

Hence, the height of the cliff is, h = 78.4 m

8 0

2 years ago