Answer:
50 lb
Explanation:
Given,
The weight of astronaut's life support backpack on Earth (w) = 300 lb
Acceleration due to gravity on Earth (g) = 9.8 m/s²
Acceleration due to gravity on Moon = g'

We know that weight of an object on Earth is,


Similarly, weight on Moon will be




Thus the astronaut's life support backpack will weigh 50 lb on Moon.
Answer:
Work done to pull the piano upwards is 401250 J
Explanation:
Work is done against the gravity to pull the piano upwards
So here we can say that work done is

here we know that

also we know that
H = 75 m
now we have


Answer:
Explanation:
For fundamental frequency in a vibrating string , the formula is
n = 1 / 2L x √ ( T /m₁ )
n is frequency , L is length , T is tension and m₁ is mass per unit length .
For first string ,
293 = 1 / 2L x √ ( 49 N /m₁ )
For second string , let mass per unit length be m₂ .
196 = 1 / 2L x √ ( 49 N /m₂ ) ------ ( 1 )
To bring its frequency back to previous one let tension be T
293 = 1 / 2L x √ ( T /m₂ ) ------- ( 2 )
Dividing
293 / 196 = √ ( T /49 )
1.4948 = √ ( T /49 )
2.2344 = T /49
T = 109.48 N .
A ) v = v o - a t
0 = 22 - a · t
a · t = 22
d = v o · t - a t²/2
0.04 = 22 t - 22 t / 2
0.04 = 11 t
t = 0.04 : 11 = 0.003636 s
a = 22 / t
a = 6050 m/s²
F = m · a = 0.09 kg · 6050 m/s²
F ( target→arrow) = - 544.5 N
b ) F ( arrow→target ) = 544.5 N
c ) If the speed was doubled: v = 44 m/s;
F = a m
a = 6050 m/s²
a · t = 44
t = 6050 : 0.04
t = 0.007272 s
d = 44 t - 44 t/2 = 22 t
d = 22 · 0.007272
d = 0.16 m = 16 cm