A ball is spun around in circular motion such that its frequency is 10 Hz.
a. What is the period of its rotation?
b. How much time will be required to complete 100 rotations?
Answer:
a = 0.1 s b. 10 s
Explanation:
Given that,
The frequency in circular motion, f = 10 Hz
(a) Let T is the period of itsrotation. We know that,
T = 1/f
So,
T = 1/10
= 0.1 s
(b) Frequency is number of rotations per unit time. So,
[tex]t=\dfrac{n}{f}\\\\t=\dfrac{100}{10}\\\\t=10\ s[/tex]
Hence, this is the required solution.
Which element is the biggest contributor to Climate Change?
Answer:
carbon dioxide (CO2)
Explanation:
the burning or combustion of these fossil fuels creates gases that are released into the atmosphere. Of these gases, carbon dioxide (CO2) is the most common and is the gas most responsible for exacerbating the green- house effect that is changing global climate patterns.
A spherical light bulb dissipates 100W and is of 5cm diameter. Assume the emissivity is 0.8 and the irradiation is negligible. What is the surface temperature of this spherical light bulb
Answer:
[tex]T=728.9K[/tex]
Explanation:
Power [tex]P=100W[/tex]
Diameter [tex]d=5[/tex]
Radius [tex]r=2.5cm=>2.5*10^{-2}m[/tex]
Emissivity [tex]e=0.8[/tex]
Generally the equation for Area of Spherical bulb is mathematically given by
[tex]A=4\pi r^2[/tex]
[tex]A=4\pi (2.5*10^{-2}m)^2[/tex]
[tex]A=7.85*10^{-3}m^2[/tex]
Generally the equation for Emissive Power bulb is mathematically given by
[tex]E=e\mu AT^4[/tex]
Where
[tex]\mu=Boltzmann constants\\\\\mu=5.67*10^{-8}[/tex]
Therefore
[tex]T^4=\frac{E}{e\mu A}[/tex]
[tex]T^4=\frac{100}{0.8*5.67*10^{-8}*7.85*10^{-3}m^2}[/tex]
[tex]T=^4\sqrt{2.80*10^{11}}[/tex]
[tex]T=728.9K[/tex]
Allison pulls a sled up a hill, which has an incline of 20 degrees to the horizontal. Of the sled has a mass of 20 kg, and the coefficient of kinetic friction between the sled and the ground is 0.1, what is the minimum force Allison must apply to the sled to keep it moving forward at a constant speed
Answer:
[tex]F=48.62N[/tex]
Explanation:
From the question we are told that:
Angle [tex]\theta= 20[/tex]
Mass [tex]m= 20kg[/tex]
Coefficient of kinetic friction [tex]\mu=0.1[/tex]
Generally the equation for Force Required to jeep sled moving is mathematically given by
[tex]F= mg sin \theta - \mu N[/tex]
Where N is normal force
[tex]F_N=Wcos\theta[/tex]
[tex]F_N=20*9.8*cos 20[/tex]
[tex]F_N=184.18N[/tex]
Therefore
[tex]F= (20*9.8) sin 20 - (0.1) (184.18)[/tex]
[tex]F=48.62N[/tex]
An object travels down a ramp at a constant acceleration. The object experiences a force of friction and a gravitational force. Which of the following could be true about the motion of the object?
a. The force of friction acts in the same direction as the object travels.
b. The force of friction between the surface and the object is less than the component of the gravitational force that is parallel to the ramp.
c. If the object increased in mass, the object's acceleration would change.
d. If the object increased in mass, the normal force exerted on the object would remain the same.
Answer:
Option (b) is correct.
Explanation:
An object travels down a ramp at a constant acceleration.
Friction force and the gravitational force is there.
(a). It is false. As the friction acts in the opposite direction of motion of the object.
(b). It is true. As the object moves down the ramp so the force of friction is less the component of gravitational force along the ramp.
(c). It is false. the acceleration does not depends on the mass.
a = g sin A - u g cos A
where, A is the angle of inclination and u is the coefficient of friction.
(d). It is false. The normal force is given by
N = m g cos A
so it depends on the mass.
which wave characteristic is the same for all electromagnetic waves traveling through a vacuum?
Answer:
All waves travel at the same speed c.
in a Mercury thermometer the level of Mercury Rises when its bulb comes in contact with a hot object what is the reason for this rise in the level of Mercury
Answer:
because thermometric liquid readily expands on heating or contracts on cooling even for a small difference in the temperature of the body.
