Answer:
a. 8.96 m/s b. 1.81 m
Explanation:
Here is the complete question.
a) A long jumper leaves the ground at 45° above the horizontal and lands 8.2 m away.
What is her "takeoff" speed v
0
?
b) Now she is out on a hike and comes to the left bank of a river. There is no bridge and the right bank is 10.0 m away horizontally and 2.5 m, vertically below.
If she long jumps from the edge of the left bank at 45° with the speed calculated in part a), how long, or short, of the opposite bank will she land?
a. Since she lands 8.2 m away and leaves at an angle of 45 above the horizontal, this is a case of projectile motion. We calculate the takeoff speed v₀ from R = v₀²sin2θ/g. where R = range = 8.2 m.
So, v₀ = √gR/sin2θ = √9.8 × 8.2/sin(2×45) = √80.36/sin90 = √80.36 = 8.96 m/s.
b. We use R = v₀²sin2θ/g to calculate how long or short of the opposite bank she will land. With v₀ = 8.96 m/s and θ = 45
R = 8.96²sin(2 × 45)/9.8 = 80.2816/9.8 = 8.192 m.
So she land 8.192 m away from her bank. The distance away from the opposite bank she lands is 10 - 8.192 m = 1.808 m ≅ 1.81 m
Answer:
Q = 1057.5 [cal]
Explanation:
In order to solve this problem, we must use the following equation of thermal energy.
where:
Q = heat energy [cal]
Cp = specific heat = 0.47 [cal/g*°C]
T_final = final temperature = 32 [°C]
T_initial = initial temperature = 27 [°C]
m = mass of the substance = 450 [g]
Now replacing:
![Q=450*0.47*(32-27)\\Q=1057.5[cal]](https://tex.z-dn.net/?f=Q%3D450%2A0.47%2A%2832-27%29%5C%5CQ%3D1057.5%5Bcal%5D)
Answer:
Er = 231.76 V/m, 27.23° to the left of E1
Explanation:
To find the resultant electric field, you can use the component method. Where you add the respective x-component and y-component of each vector:
E1:
E2:
Keep in mind that the x component of electric field E2 is directed to the left.
∑x: 
∑y: 
The magnitud of the resulting electric field can be found using pythagorean theorem. For the direction, we will use trigonometry.
or 27.23° to the left of E1.
Answer:
The atom becomes a positively charged ion.
Explanation:
- The building blocks of an atom are protons, neutrons, and electrons.
- The protons and neutrons present in the core of the atom are called nucleus.
- The electrons are scattered in an ordered way around the nucleus.
- The protons are positively charged and the electrons are negatively charged particles. The neutrons do not possess any charges.
- Binding energy is supplied to the atom to remove an electron.
- It is possible to remove the electrons of the lighter elements.
- When an electron is removed from the hydrogen atom. It becomes positively charged ion or simply proton.
- When all of the electrons are removed from the helium atom, it becomes a positively charged α particle.
- It is practically very difficult to remove all of the electrons from the heavier elements.
- When all of the electrons are removed from an atom it becomes an unstable positively charged ion.
Speed = distance / time
S= 40 000m / 5400s
S= 7.41m/s
