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olchik [2.2K]
3 years ago
7

a car advertisement states that a certain car can accelerate from rest to 70km/h in 7 seconds. find the cars acceleration

Physics
1 answer:
ELEN [110]3 years ago
4 0
<span>a = (v2 - v1)/t= acceleration formula

a = (70 - 0)/7
a = 10 km/hr/sec
-----
It's better to use as few units as possible.
10 km/hr = 10 km*1000 m/km/(1 hr*3600 sec/hr) = 25/9 m/sec
a= 25/9 m/sec/se</span>
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A ski lift is used to transport people from the base of a hill to the top. If the lift leaves the
Liono4ka [1.6K]
The energy of the ski lift at the base is kinetic energy:
K= \frac{1}{2}mv^2
where m is the mass of the ski lift+the people carried, and v=15.5 m/s is velocity at the base.
As long as the ski lift goes upward, its velocity decreases and its kinetic energy converts into potential energy. Eventually, when it reaches the top, its final velocity is v=0, so no kinetic energy is left and it has all converted into gravitational potential energy, which is 
U=mgh
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mgh =  \frac{1}{2}mv^2
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8 0
3 years ago
Define refractive index.​
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8 0
2 years ago
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Answer:

1.31498 kg

0.72050 s

0.72050 s

Explanation:

m = Mass of block

g = Acceleration due to gravity = 9.81 m/s²

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x = Displacement = 0.129 m

The force balance is

mg=kx\\\Rightarrow m=\dfrac{kx}{g}\\\Rightarrow m=\dfrac{100\times 0.129}{9.81}\\\Rightarrow m=1.31498\ kg

The mass of the block is 1.31498 kg

Time period is given by

T=2\pi\sqrt{\dfrac{m}{k}}\\\Rightarrow T=2\pi\sqrt{\dfrac{1.31498}{100}}\\\Rightarrow T=0.72050\ s

The period of oscillations is 0.72050 s

The time period does not depend on the acceleration due to gravity. It varies with the mass and the spring constant.

Hence, the time period would be the same

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3 years ago
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Answer: 2 seconds

Explanation:

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Answer:

I would agree with the statement. it's not just the body, but everything that we see is almost 99.9999% empty space

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