Answer: An jack makes changing a tire easier because it lifts up the car to get the tire off of the ground.
Explanation:
Answer:

Explanation:
As we know that the formula of range is given as

now we know that
maximum value of the range of the projectile is given as

now we need to find such angles for which the range is half the maximum value
so we will have




Kinetic energy is energy that a body possesses by virtue of being in motion, there for if an object is moving, it has kinetic energy.
Example; A roller coaster sitting on top of hill has potential energy. When it starts to move and is going down the hill, it has kinetic energy. :)
Answer:
Resistivity ρ=1.12 x 10^-4 Ωm
Explanation:
ρ= RA/l, where R is resistance, A is cross sectional area and l is length
A=πr^2
Note Current is given R is proportion to temperature and inversely proportional to Current R=(20+273)/14*10^-2 =2000Ω
⇒ρ=R*πr^2/l all length in metre.
12.00 min = 0.2 hr
8.00 min = 0.15 hr
Total distance:
(10.0 km/hr) (0.2 hr) + (15.0 km/hr) (0.15 hr) + (20.0 km/hr) (0.2 hr)
= 8.25 km
Average speed:
(10.0 km/hr + 15.0 km/hr + 20.0 km/hr) / 3
= 15 km/hr
Change in position:
(10.0 km/hr) (0.2 hr) + (15.0 km/hr) (0.15 hr) - (20.0 km/hr) (0.2 hr)
= 0.25 km
Average velocity:
(10.0 km/hr + 15.0 km/hr - 20.0 km/hr) / 3
≈ 1.67 m/s